Systematic review and meta-analysis of eccentric-only versus concentric-only strength training effects on maximal voluntary eccentric, concentric and isometric contraction strength

Systematic review and meta-analysis of eccentric-only versus concentric-only strength training effects on maximal voluntary eccentric, concentric and isometric contraction strength | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Systematic review and meta-analysis of eccentric-only versus concentric-only strength training effects on maximal voluntary eccentric, concentric and isometric contraction strength Darjan Spudić, Kazunori Nosaka This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4385283/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 21 Aug, 2025 Read the published version in Sports Medicine-Open → Version 1 posted 5 You are reading this latest preprint version Abstract Background Conflicting results have been reported regarding the effects of resistance exercise training with eccentric (lengthening muscle) versus concentric (shortening muscle) contractions on changes in muscle mechanical function assessed by different contraction modes. Objective The main objective of this systematic review with meta-analyses was to compare effectiveness of maximal isokinetic eccentric-only and concentric-only strength training for changes in maximal voluntary eccentric (MVC ECC ), concentric (MVC CON ), and isometric contraction (MVC ISO ) strength in healthy adults. Methods We conducted a systematic search in PubMed, SPORTDiscus, and Google Scholar from February to March 2024 for studies that met the following criteria: (1) randomized controlled trials; (2) inclusion of eccentric-only and concentric-only strength training groups; (3) use of an isokinetic dynamometer for training and testing; (4) reporting changes over time in MVC CON and MVC ECC ; and (5) using healthy adult participants. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. A multilevel random-effects model meta‑analyses with robust variance estimation were performed in Rstudio software using metaphor and clubSandwich packages. Moreover, sensitivity analysis was performed, excluding the highly influential studies. The potential moderating role of sex, training status and age of the participants, muscles, velocity in training and testing, initial MVC ECC , MVC CON , and MVC ECC /MVC CON ratio, and training-related variables such as number of repetitions per set, number of sets, number of sessions per week, and duration of the training protocol were also assessed. Results Twenty-seven studies matched with the criteria, and overall 162 study results were identified and included in the meta-analyses. Greater effects on MVC ECC was found after eccentric-only versus concentric-only training (Hedge’s g: 1.51; 27% vs. 10%; p < .05). However, no differences were evident between the training modalities for changes in MVC CON (Hedge’s g: − 0.10; 13% vs. 14%, p = .726) and MVC ISO (Hedge’s g: − 0.04; 18% vs. 17%; p = .923). The subgroup analyses showed smaller effect of eccentric-only than concentric-only training on MVC CON when eccentric-only training was performed at higher velocities than the velocities of MVC CON testing (Hedge’s g: − 0.99; p < .05). Meta-regressions showed that the longer the training period, the greater the superior effect of eccentric over concentric training on MVC ECC . Conclusions Eccentric-only strength training is more effective for improving MVC ECC , but both concentric-only and eccentric-only training provide similar effects on improving MVC CON and MVC ISO . Further studies are necessary to investigate the mechanisms underpinning the superior effect of eccentric-only training. lengthening shortening muscle contraction training mode strength training specificity resistance exercise Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Key Points Eccentric-only strength training is more effective than concentric-only strength training for increasing maximal voluntary eccentric contraction strength (27% vs 10%). The superiority of eccentric-only training for improving maximal voluntary eccentric contraction strength becomes more prominent with longer training periods, but the effect of faster velocity maximal eccentric-only training on slower maximal voluntary concentric contraction strength is limited. Eccentric-only and concentric-only strength training similarly increase maximal voluntary concentric and isometric contraction strength, thus eccentric-only training appears to produce more versatile effects than concentric-only training. Maximal eccentric-only training methods should be actively promoted among strength and conditioning practices to effectively enhance eccentric strength and the movements dependent on it. 1 Introduction Muscle strength is crucial not only for athletic performance [ 1 ] but also for health and quality of life [ 2 ]. Resistance training is the most effective way to increase muscle strength, and its optimal protocols to increase muscle strength more effectively have been investigated [ 3 ]. Since neuromuscular and functional changes induced by resistance training differ in contraction modes [ 4 ], it has been a topic of interest [ 5 ]. In resistance exercises, eccentric (lengthening muscle), concentric (shortening muscle), and isometric (static) contractions are used, and all of them increase muscle strength [ 6 ]. However, it is not necessarily clear how the contraction modes used in a training affect strength gains in different contraction modes after the training [ 7 ]. Maximal voluntary eccentric contraction strength (MVC ECC ) is more than 40% greater than maximal voluntary concentric contraction strength (MVC CON ) in isokinetic contractions [ 8 ]. This makes eccentric contractions more advantageous than concentric contractions, since it is possible to impose greater mechanical stimulus to muscles by eccentric contractions, producing better effects on peripheral and central adaptations that underpin muscle strength increase [ 9 ]. Resistance exercises with eccentric contractions (i.e., eccentric resistance exercises) appear to activate satellite cells and muscle protein synthesis pathways, resulting in a greater increase in the number of sarcomeres in parallel and in series [ 10 , 11 ]. Moreover, during eccentric contractions, passive muscular tension is generated by lengthening the extracellular matrix and titin [ 12 ]. The combined tension from contractile and noncontractile elements strengthens not only the muscle [ 12 ] but also noncontractile elements including tendons [ 13 ]. It appears that most of the strength gains in shorter than eight weeks of eccentric training are more attributable to increased neural drive [ 14 ], possibly due to the more robust downregulation of peripheral inhibitory pathways and higher activity of the central nervous system [ 4 , 15 ] indicated by an increased motor unit discharge rate [ 16 ]. Due to its potent effects and the advent of new technologies [ 17 ], eccentric resistance exercises including those consisting of eccentric-only contractions (concentric contractions are performed without load or with a minimal load) are becoming increasingly prevalent in strength training, rehabilitation, and injury prevention programs [ 18 ]. However, considerable methodological variations exist in the studies comparing the effects of eccentric versus concentric strength training, which makes conclusions regarding the eccentric versus concentric strength training effects challenging [ 5 , 10 ]. The variability stems from the specificity of strength measurements such as one-repetition maximum (1-RM) and maximal voluntary contraction force/torque; training modalities (e.g., isokinetic, isoinertial, and isoweight [ 18 ]), muscles trained (e.g., upper body, lower body), and training-related variables including number of repetitions per set, sets per session, frequency of training, duration of the training protocols, and exercise tempo or velocity [ 7 , 19 , 20 ]. Participant characteristics such as age [ 21 ], training status, and initial strength [ 22 ], also contribute to this variability. Given that eccentric contractions have higher force generation capability and fatigue tolerance [ 23 ], optimal loading during the training should consider these characteristics. Previous meta-analysis studies have shown favourable effects of eccentric over concentric resistance exercise training on muscle hypertrophy [ 5 , 24 ]. Moreover, the meta-analysis study by Roig et al. [ 5 ] identified favourable effects of eccentric-only strength training on MVC ECC , but did not find significant differences between the two in changes in MVC CON and maximal voluntary isometric strength (MVC ISO ). They concluded that the better effects of eccentric-only over concentric-only training were produced by maximal but not submaximal contractions performed in the training [ 5 ]. They also stated that eccentric-only strength training adaptations were more velocity-specific. However, the authors included only two effect sizes in the subgroup analysis of velocity specific adaptations [ 5 ]. As the magnitude of MVC ECC to MVC CON ratio is known to be influenced by factors such as age, muscle groups assessed, testing velocity, and sex [ 8 ] and while different training modalities (e.g., isokinetic dynamometry, free weights) were used for training and testing in various studies included in the review, these could have affected the overall heterogeneity of the results. These should be considered to compare eccentric-only and concentric-only resistance training for their effects on muscle strength. Eccentric training has been proposed to improve muscle mechanical function to a greater extent than other contraction modes [ 5 , 9 – 11 , 25 ]; however, the quantification of this effect remains unknown. To investigate the effects of the muscle contraction mode on changes in muscle strength, we thought that the most reliable way would be to perform meta-analyses of existing studies in which compared maximal eccentric-only and concentric-only strength training using an isokinetic dynamometer for changes in changes in MVC ECC , MVC CON , and MVC ISO strength. Therefore, the main aim of the present systematic review and meta-analyses was to examine the hypothesis that eccentric-only strength training would provide superior effects on not only MVC ECC but also MVC CON and MVC ISO strength when compared with concentric-only strength training. Additionally, changes in MVC CON , MVC ECC , and MVC ISO strength were compared within eccentric-only and concentric-only maximum isokinetic contraction training groups to evaluate the transferability of the strength training on strength measures in different contraction modes. We hypothesized that eccentric-only strength training would produce greater increases in not only MVC ECC strength but also MVC CON and MVC ISO strength when compared with concentric-only strength training, thus eccentric-only strength training would produce greater transferable strength effect on different contraction modes. 2 Materials and Methods 2.1 Study design This systematic review followed the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” guidelines [26]. A review protocol was not pre-registered for this review. 2.2 Search strategy To identify all potentially relevant data from the experimental studies, an initial systematic literature searches were conducted between February and March in 2024, with no limitations based on publication date. Searches included the following databases: MEDLINE/PubMed, SPORTDiscus, and Google Scholar. Moreover, we used “snowballing” strategies (i.e., reference screening from most relevant studies and citation tracking using a scholarly publication discovery tool supported by artificial intelligence, Research Rabbit [27]) as described by Greenhalgh and Peacock [28]. Electronic databases were searched using the combination of the following search terms: (eccentric or lengthening) AND (shortening or concentric) AND (exercise or training) AND (strength or torque or force or isokinetic or isometric or muscle). 2.3 Data extraction Articles were screened following a three-stage process: (1) duplicates of articles identified across numerous search databases were removed; (2) article title and abstracts were screened for suitability. Where a definitive decision could not be made at this stage, studies were taken forward for a full study review; and (3) full articles were screened according to the inclusion and exclusion criteria. All of these were done by one of the authors (DS). 2.4 Eligibility criteria Studies were considered to be eligible for inclusion according to the PICOS criteria (Participants, Intervention, Comparator, Outcome, and Study design). The articles that used healthy (i.e., the absence of injury or illness) adult (i.e., 18–64 years) human participants were chosen. Only randomized controlled exercise intervention studies including both eccentric-only ( intervention ) and concentric-only strength training protocols ( comparator ) were included. Training and testing were required to be performed on an isokinetic dynamometer. The primary outcomes were percentage changes (mean and standard deviation) in MVC CON and MVC CON before and after training. The secondary outcome was percentage change in MVC ISO , if reported. Only studies with randomized design and published in peer-reviewed journals were qualified to be included. If the aforementioned criteria were not fulfilled, or if the strength training protocol was not defined appropriately, or if strength measures were taken outside the training joint range of motion area [29,30], they were excluded. Studies from which we could not extract enough information to calculate the effect size and include them in the qualitative data synthesis were also excluded. Data were extracted by one investigator (DS). Consensus or arbitration by a second investigator (KN) was used to settle any disputes [26]. If a study did not report percent changes and standard deviation of the change within both training groups (for example only means and standard deviations for pre- and post-intervention within each group were reported or only raw change with SD was reported), we calculated the percent change and SD of the percent change relative to the baseline raw value within each group. Finally, for papers in which data were presented in figures, muscle strength values were estimated using a graph digitizer (WebPlotDigitizer, https://apps.automeris.io/wpd/). In accordance with the recommendation for meta-analysis [31], in case of incomplete data, we calculated missing change score SDs (SDchange) from SD values at baseline (SDpre) and postintervention (SDpost) using the following formula: √((SDpre^2/N)+(SDpost^2/N)); where N was the number of participants. In one study only change over time in raw values was reported [32] for training groups and a control group (which did not train). In this case, percent improvement of the eccentric training and concentric training groups were calculated regarding to control group results using the formula ((eccentric or concentric–control group)/control group)*100. In addition to main outcomes, the extracted data from papers included study type (randomized controlled trial or cross design randomized controlled trial); sample size (for eccentric and concentric training groups), sex of the participants (male, female, mixed sample); age of the participants (years), training status of the participants (untrained, moderately trained, trained); muscles trained and tested; testing and training isokinetic velocity (°/s); joint angle of strength assessment (only in the case of MVC ISO; in degrees [°]); number of repetitions per set; number of sets per session; training frequency (number of sessions per week); duration of the training (in weeks) and participants’ initial MVC CON and MVC CON [force or torque, not normalized to body mass]. Additionally, initial eccentric to concentric strength ratio was calculated from the initial MVC ECC and MVC CON data. 2.5 Methodological quality assessment The Physiotherapy Evidence Database scale (PEDro), TIDieR (Template for Intervention Description and Replication) and, finally, Grading of Recommendations Assessment, Development and Evaluation (GRADE) checklists were used to assess the risk of bias, completeness of intervention descriptions and quality of evidence, respectively. Using the PEDro scale [33], the listed studies’ methodological quality was evaluated by the investigator (DS). The PEDro scale consists of 11 items designed to assess methodological quality. Studies were categorized as at low risk (≥ 6 points), moderate risk (4–5 points), and high risk (≤ 3 points) of bias. The intervention descriptions were evaluated for completeness using the TIDieR checklist [34]. Finally, the GRADE approach was used to evaluate the oveall quality of the evidence [35,36]. Quality assessement was perfomed separately for each meta-analysis (Table S3 of the ESM). High quality of evidence was initially assumed and then downgraded based on the following criteria: a) risk of bias (downgraded by one level if the median PEDro score was indicative of moderate risk (4 or 5 points) or two levels if scoe was indicative of high risk (< 4 points), b) inconsistency, downgraded by one level if the Cochrane Q test for heterogeneity was significant (p<0.05) or total I 2 exceeded 50%; c) indirectness was considered at low risk, because the PICOS criteria were ensured; d) imprecision [37], downgraded by one level if the confidence interval was large and crossed by a small effect size [−0.2 to 0.2] or [−5 to +5%] considering as and important strenght change over time, and d) publication bias, downgraded by one level if Egger’s test, assessing the asymmetry in the funnel plot was significant (p<0.10). The level of certainty was considered as high (considerable confidence exists that the true effect is similar to the estimated effect), moderate (true effect is probably close to the estimated effect), low (true effect might be markedly different from the estimated effect), or very low (true effect is probably markedly different from the estimated effect). 2.6 Statistical analyses While some studies provided multiple outcomes, multilevel random-effects model meta‑analyses with robust variance estimation were preformed to control for dependent effect sizes in a meta-regression models [38,39]. Following the main objective of our research, MVC ECC , MVC CON and MVC ISO changes following the eccentric-only and concentric-only training protocols were compared in separate meta-analyses. Standardized mean differences as Hedge’s g (effect size corrected for sample size) with 95% CIs between eccentric-only training and concentric-only training protocols were calculated for individual studies and to test for overall effect. The following categories were used to categorize the size of the effects: trivial (4.00) [40]. Forest plots were displayed to graphically represent effects of each individual study, the magnitude of overall effect and its direction (favouring eccentric or concentring training). To aid interpretation of the findings, separate multilevel random-effects model meta‑analyses of single means with robust variance estimation were used to synthesize the percent (%) outcomes from individual studies for improvements of MVC ECC , MVC CON and MVC ISO after eccentric-only and concentric-only training protocols. Percent improvements of MVC ECC , MVC CON and MVC ISO were additionally compared within the training mode by pairwise meta‑analyses (improvement of MVC ECC vs. MVC CON vs. MVC ISO , separately for eccentric and concentric training, respectively) to observe the effect of mode-specificity of the training. Publication bias was evaluated with observing asymmetry of the funnel plots by calculating the Egger’s statistics. A substantial publication bias was regarded when the p-value was less than 0.10. Moreover, heterogeneity was investigated using the Cochrane Q-test (Chi 2 statistics), σ 2 test (sigma 2 ; variance normalized to effect sizes) and the I 2 (relative measure of heterogeneity among studies; %). Values of 25, 50, and 75% for I 2 signified low, moderate, and high statistical heterogeneity [41]. The heterogeneity was additionally partitioned across two levels (i.e., Level 2: within-study and Level 3: between-study heterogeneity). For all meta-analytic models, influential case diagnostics were performed to identify studies that have a large influence on the overall effect size. Cook’s distance, which combines information about both the leverage and outliers’ impact on the analysis was calculated to identify if particular study effect size had a potential effect on the estimated coefficients. Individual cases were red flagged if Cook’s distance’s values exceeded more than three times their respective mean. Robustness of each meta-analysis model was checked with sensitivity analysis, excluding red-flagged studies from the analysis. To explain the variation of the effects, subgroups analyses were performed for categorical variables: sex [male, female, mixed]; muscle trained [upper body, lower body]; training status of the participants [untrained, moderately trained, highly trained] and training to testing isokinetic velocity [with four categories: training at lower velocity than the testing, training at higher velocity than the testing, training at the same velocity as the testing and velocity spectrum pyramidal ordering concept training] (please see Table 1 for explanation). Moreover, to explain the variation of the effects by continuous moderator variables random-effects meta-regressions were performed. These moderators were separated into participant-related ( age of the participants, initial MVC CON , initial MVC ECC and initial MVC ECC /MVC CON ratio) and into training-related moderators (number of repetitions per set, number of sets , number of training sessions per week and duration of the resistance training protocol in weeks). For training-related moderators, multiple meta-regression was performed to distinguish the effect of each training-related variable on the effect size while holding other training-related variables constant. The estimated proportional reduction in the total variance was computed using the variance accounted for, a pseudo R 2 value (i.e., the amount of heterogeneity accounted for by the moderator(s)). Meta-analyses were performed in the RStudio: Integrated Development Environment for R (v4.3.3.; Posit team [2024], Boston, MA; http://www.posit.co/, accessed in April 2024). The robust variance estimation method was implemented using the clubSandwich package. Sampling variance-covariance matrix was prepared with estimating 0.6 degree of correlation between sample variances of different outcomes within a study. The matrix was then included into the metaphor package. Moreover, confidence intervals of robust meta-analyses were obtained by adjusting for small samples. The cut-off for statistical significance was set at p < 0.05 [40]. 3 RESULTS 3.1 Search results The initial search yielded 6,614 studies, and we observed that using different search terms to narrow them could overlook some of the of the most relevant research. Therefore, we adopted a more conservative approach. Identified records were filtered using keywords in titles and abstracts through the systematic review software Rayyan [42] (https://www.rayyan.ai/, accessed in March 2024). Additionally, reference screening was performed on the most relevant studies, and citation tracking was conducted using Research Rabbit software [27] (https://www.researchrabbit.ai/, accessed in March 2024), which yielded an additional 50 potentially useful studies. Our systematic review and meta-analysis ultimately included 27 studies. Of these, 11 studies reported changes in all three strength measures (MVC ECC , MVC CON , and MVC ISO ) following both concentric-only and eccentric-only training. However, 16 studies did not report changes in MVC ISO . In total, we gathered 162 study results (expressed as changes in percent units). This enabled us to calculate 71 standardized effect sizes for differences in improvements of MVC ECC and MVC CON between both training groups (71 results in each group) and 20 standardized effect sizes for differences in improvements of MVC ISO between training groups (20 results in each group). To aid interpretation of the findings, results of multiple studies within each training group and contraction mode were summarized and compared in separate meta-analyses. The stages of the search and study selection process are presented in Fig. 1. 3.2 Study characteristics Individual study characteristics are presented in Table 1. Summary of study characteristics reporting MVC CON and MVC CON by categorical subgroup variables are presented in Table 2. The summary of study characteristics by categorical subgroup variables for the studies reporting MVC CON , MVC CON and additionally MVC ISO are presented in Table 3. Additionally, in studies reporting MVC CON and MVC ECC (Table 2), the number of repetitions per set ranged from 1 to 15 (mode = 10; mean ± SD = 9.6 ± 2.4), the number of sets ranged from 1 to 7 (mode = 3; mean ± SD = 4.7 ± 1.6), the number of training session per week ranged from 1 to 5 (mode = 3; mean ± SD = 2.8 ± 0.6) and training protocol duration ranged from 4 to 20 weeks (mode = 6; mean ± SD = 7.8 ± 3.8). The mean age of the participants was 25 years (SD = 4.7; range 20-38). The number of participants was 364 for the eccentric training group and 354 for the concentric training group. When summarizing multiple results from the same studies, the totals were 904 and 899, respectively. ** Table 1 around here ** ** Table 2 around here ** In the studies where MVC ISO was reported (Table 3), the number of repetitions per set ranged from 1 to 15 (mode = 10; mean ± SD = 9.0 ± 3.1), the number of sets ranged from 1 to 6 (mode = 3; mean ± SD = 3.7 ± 1.2), the number of training session per week ranged from 1 to 5 (mode = 3; mean ± SD = 2.9 ± 0.9) and training protocol duration ranged from 4 to 12 weeks (mode = 6; mean ± SD = 6.4 ± 2.0). The mean age of the participants was 23.3 years (SD = 1.3; range 21-28). The number of participants was 111 for the eccentric training group and 110 for the concentric training group. When summarizing multiple results from the same studies, the totals were 215 and 215, respectively. ** Table 3 around here ** 3.3 Quality of evidence and completeness of reporting PEDro scale values and completeness of reporting of the controlled randomized study items are presented for each particular study in Table 1. PEDro scores ranged from 5 to 9 (mode = 6; mean ± SD = 6.3 ± 1.0) indicating low to moderate risk of bias (Table S1 of the ESM). As shown in Figure 2, all studies reported the execution of the testing and training procedures, but only 19% reported who performed the training or testing protocol, 44% clarified where the training and testing was performed, 15% clarified if sample size was calculated, and 37% of the studies reported information regarding the dropout of the participants. None of the studies reported tailoring and/or modifications of training protocols (Table S2 of the ESM). Altogether, due considerable heterogeneity (Q test results) and publication bias (Egger’s statistics; further reported in text following the results of the particular meta-analysis results and summarized in Table S3 of the ESM), quality of evidence were downgraded from high quality to low quality according to GRADE approach [36] for MVC ECC results. Additionally, due to imprecision (confidence interval was crossed by a small effect size), MVC CON and MVC ISO results were downgraded to very low quality. 3.4 Meta-analyses results 3.4.1 Effect of different resistance training modes on eccentric strength gain (MVC ECC ) A meta-analysis of 27 studies with 71 comparisons showed statistically significantly beneficial effects of eccentric-only in comparison to concentric-only strength training for improvement of MVC ECC (Hedge’s g = 2.03, 95% CI: 0.74 to 3.32; p < 0.01; very large effect) (Figure S1 of the Electronic Supplementary Material [ESM]). A small sample adjustment to the robust meta-analysis results expanded the confidence intervals of Hedge’s to 0.69 to 3.39. Five individual effect sizes from two studies were identified as highly influential. However, the overall results were robust to their exclusion from the model as the interpretation of the model did not change. Overall Hedge’s g decreased to 1.51 (95% CI: 0.59 to 2.42; p < 0.01; large effect), with the small sample adjustment for the 95% CI being 0.55 to 2.47 (Fig. 3). Egger’s test results indicated publication bias for the MVC ECC (p<0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 647.9, df = 65; p < 0.01; I 2 = 96.5%). Within study effect size variability (Level 2) was low to moderate (29%), while between study variability (Level 3) was moderate to high (68%). 3.4.2 Effect of resistance training modes on concentric strength gain (MVC CON ) A meta-analysis of 27 studies with 71 comparisons did not show statistically significantly different benefits of eccentric-only and concentric-only strength training for improvement of MVC CON (Hedge’s g = –0.71, 95% CI –1.65 to 0.22; p = 0.13; small effect) (Figure S2 of the ESM). A small sample adjustment to the robust meta-analysis results expanded the confidence intervals of Hedge’s to –1.69 to 0.27. Five individual effect sizes from three studies were identified as highly influential. However, the overall results were robust to their exclusion from the model as the interpretation of the model did not change. Overall Hedge’s g decreased to trivial, i.e. –0.10 (95% CI: –0.69 to 0.48) with small sample adjustment 95% CI ranging from –0.72 to 0.51 (Fig. 4). Egger’s test results indicated publication bias for the MVC CON (p<0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 358.4, df = 65; p<0.01; I 2 = 92%). Within study effect size variability (Level 2) was low (21%), while between study variability (Level 3) was moderate to high (71%). 3.4.3 Effect of resistance training modes on isometric strength gain (MVC ISO ) A meta-analysis of 11 studies with 20 comparisons did not show statistically significantly different effects between eccentric and concentric resistance training protocols for improvement of MVC ISO (Hedge’s g = –0.31, 95% CI –2.40 to 1.75; p = 0.77; small effect) (Figure S3 of the ESM). A small sample adjustment to the robust meta-analysis results expanded the confidence interval (Hedge’s g = –0.31, 95% CI –2.65 to 2.02). Two individual effect sizes from two studies were identified as highly influential. After removing them from the analysis, the overall effect size changed sign and narrowed the confidence intervals from negative (favouring concentring training) to positive trivial (Hedge’s g: 0.04 with 95% CI: –0.82 to 0.90), favouring eccentric training (Fig. 5). Confidence intervals (95%) for robust meta-analysis with small samples adjustment ranged from –0.96 to 1.05. Egger’s test results indicated publication bias for the MVC ISO (p<0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 120.7, df = 25; p<0.01; I 2 = 89%). Within study effect size variability (Level 2) was low (11%), while between study variability (Level 3) was moderate to high (71%). 3.4.4 Analyses of moderators Despite high statistical heterogeneity among the studies comparing the magnitude of increase of MVC ECC between eccentric and concentric training, no statistically significant differences were found within subgroups of sex (Chi 2 = 3.2; p = 0.20; pseudo R 2 = 2.7%), muscle (Chi 2 = 0.59; p = 0.44; pseudo R 2 = 6%), and training status (Chi 2 = 0.89; p = 0.83; pseudo R 2 = 18%). Effect of eccentric-only training was more superior when testing was performed at the same velocity as training in comparison to when testing was performed at the lower velocity as the training (difference of 1.53 in Hedge’s g, p<0.05), nevertheless training to testing isokinetic velocity subgroups together could not explain the variability of the effect (Chi 2 = 7.2; p = 0.07; pseudo R 2 = 1%). Participant-related continuous moderators analyses showed no effect of age (Chi 2 = 3.0; p = 0.08; pseudo R 2 = 12.7%), initial MVC ECC (Chi 2 = 0.16; p = 0.69, pseudo R 2 = 10%), initial MVC CON (Chi 2 = 0.55; p = 0.46, pseudo R 2 = 12%) and MVC ECC /MVC CON ratio (Chi 2 = 2.05; p = 0.15; pseudo R 2 = 12%). Moreover, training related variables included in multiple meta-regression ( number of repetitions , sets , frequency and duration of training ), could not statistically significantly explain the variability (Chi 2 = 8.2; p = 0.08; pseudo R 2 = 19.5%). Within training-related factors, only duration of the training protocol had shown statistically significant influence to the effect size (β = 0.25 [95% CI: 0.05-0.45]; SE = 0.10; z = 2.4; p < 0.05). Thus, the longer the training protocol, the more beneficial the eccentric training was over concentric training for improving MVC ECC when controlling for the rest of training-related factors (Table S4 of the ESM). Comparing the magnitude of increase of MVC CON between eccentric and concentric training, no statistically significant differences were found between subgroups of sex (Chi 2 = 3.90; p = 0.14; pseudo R 2 = 4.4%), muscle (Chi 2 = 0.00; p = 0.98; pseudo R 2 = 10%) and training status (Chi 2 = 1.89; p = 0.60; pseudo R 2 = 21%). Statistically significant differences were found within subgroups of training to testing isokinetic velocity (Chi 2 = 8.4; p < 0.05; pseudo R 2 = 49%). A statistically significant lower effect of eccentric training compared to concentric training on the improvement of MVC CON was observed when the eccentric training was performed at higher velocities than those used in the MVC CON testing in comparison to the effect of the same training and testing velocity (Hedge’s g = –0.99 [95% CI from –1.75 to –0.23]; p < 0.05). Participant-related continuous moderators showed no effect of age (Chi 2 = 0.68; p = 0.41; pseudo R 2 = 13%), initial MVC ECC (Chi 2 = 0.08; p = 0.77; pseudo R 2 = 14.5%), initial MVC CON (Chi 2 = 0.19; p = 0.66; pseudo R 2 < 19.7%) and MVC ECC /MVC CON ratio (Chi 2 = 1.84; p = 0.17; pseudo R 2 = 5.2%). Moreover, training related variables ( number of repetitions , sets , frequency and duration of training ), could not statistically significantly explain the variability (Chi 2 = 5.7; p = 0.22; pseudo R 2 = 40.7 %) (Table S5 of the ESM). Among the studies comparing the magnitude of increase of MVC ISO between eccentric and concentric training, no statistically significant differences were found within subgroups of sex (Chi 2 = 0.02; p = 0.99; pseudo R 2 = 47%), muscle (Chi 2 = 0.20; p = 0.66; pseudo R 2 = 18%) and training status (Chi 2 = 2.85; p = 0.24; pseudo R 2 = 9%). Participant-related continuous moderators showed no effect of age (Chi 2 = 0.3; p = 0.60; pseudo R 2 = 14.7%), initial MVC ECC (Chi 2 = 0.10; p = 0.75, pseudo R 2 = 3.6%), initial MVC CON (Chi 2 = 0.5; p = 0.47, pseudo R 2 = 29%) and MVC ECC /MVC CON ratio (Chi 2 = 0.17; p = 0.68; pseudo R 2 = 31%). Moreover, training related variables ( number of repetitions , sets , frequency and duration of training ), could not statistically significantly explain the variability (Chi 2 = 0.65; p = 0.96; pseudo R 2 = 14%) (Table S6 of the ESM). 3.4.5 Changes in strength within training group As shown in Fig. 6, results from individual studies indicate that eccentric-only training resulted in an improvement of MVC ECC by 27.3% (95% CI: 19.4-35.2%; p<0.05; robust 95% CI: 18.2-36.4%), MVC CON by 12.6% (95% CI: 8.6-16.7%; p<0.05; robust 95% CI: 8.0-17.3%), and MVC ISO by 18.2% (95% CI: 11.7-24.7%; p<0.05; robust 95% CI: 10.2-26.2%) (Table S7 of the ESM). Improvements after concentric-only training were observed as follows: MVC ECC increased by 10.2% (95% CI: 8.2-12.3%; p<0.05; robust 95% CI: 7.2-13.2%), MVC CON by 13.8% (95% CI: 10.0-17.5%; p<0.05; robust 95% CI: 9.7-17.9%), and MVC ISO by 16.9% (95% CI: 9.5-24.2%; p<0.05; robust 95% CI: 7.8-25.9%) (Table S7 of the ESM). No influential individual results were identified, and Egger’s test results showed no publication bias, with p-values ranging from 0.08 for MVC CON after concentric training to 0.797 for MVC ISO after eccentric training. Statistically significant heterogeneity was confirmed by Q-test (p<0.05) in all cases, with I 2 values exceeding 98% in all cases. Specifically, level 2 I 2 varied from 0% for MVC ISO after concentric training to 27% for MVC CON after concentric training, while level 3 I 2 ranged from 72% for MVC CON after concentric training to 99% for MVC ISO after concentric training (Table S7 of the ESM). 3.4.5 Differences in strength changes within training group and between groups Pairwise comparisons revealed differences in strength improvement among testing contraction modes following eccentric-only training : MVC ECC versus MVC CON showed an 11.5% difference (95% CI: 11.2-11.7; robust 95% CI: –1.9 to 24.8; p<0.05), illustrated in Fig. 6. The difference between MVC ECC and MVC ISO was 8.6% (95% CI: 8.0-9.3; robust 95% CI: –44.4 to 61.7; p<0.05), and between MVC CON and MVC ISO was 3.8% (95% CI: 3.3-4.3; robust 95% CI: –5.7 to 13.2; p<0.05) (Table S8 of the ESM). For concentric-only training , the respective differences were also notable: MVC ECC versus MVC CON at 1.7% (95% CI: 1.5-1.9; robust 95% CI: 4.1-7.5; p<0.05), MVC ECC versus MVC ISO at 6.2% (95% CI: 5.7-6.7; robust 95% CI: 1.4-11.0; p<0.05), and MVC CON versus MVC ISO at 2.1% (95% CI: 1.7-2.6; robust 95% CI: –7.0 to 11.2; p<0.05) (Table S8 of the ESM). No influential individual results sizes were detected. Egger’s test revealed publication bias (p<0.10) in all comparisons except for MVC ECC versus MVC ISO after concentric training (p=0.44), and statistically significant heterogeneity was confirmed in all cases with Q-test’s Chi 2 statistics (p<0.05). I 2 values exceeded 90% for all comparisons. Specifically, level 2 (within-study) I 2 ranged from 38.6% for the MVC CON and MVC ISO comparison for concentric training to 66.4% for the MVC ECC and MVC ISO comparison post concentric training. Level 3 (between-study) I 2 ranged from 32.3% for the MVC ECC vs MVC ISO comparison post concentric training to 62% for the MVC ECC vs MVC CON comparison post eccentric training (Table S8 of the ESM). 4 Discussion The present systematic review with meta-analyses examined the hypothesis that eccentric-only strength training would increase not only MVC ECC but also MVC CON and MVC ISO greater when compared with concentric-only strength training. It was found that both eccentric-only and concentric-only strength training increased MVC ECC , MVC CON , and MVC ISO . The results of the meta-analyses partially supported the hypothesis such that eccentric-only strength training was better for increasing MVC ECC , but the increases in MVC CON and MVC ISO were not significantly different between eccentric-only and concentric-only strength training. The results also showed that the longer the training period, the greater the increase in MVC ECC by eccentric-only than concentric-only training. Moreover, higher-velocity eccentric-only training had a lower effect on slower MVC CON strength gains when compared with concentric-only higher-velocity training. 4.1 Specificity of strength gain While both eccentric-only and concentric-only strength training were effective for increasing MVC ECC , eccentric-only training led to a greater increase (27%) than concentric-only training (10%) as shown in Fig. 6 . As depicted in Fig. 3 , 29 out of 71 individual effect sizes (41%) favoured eccentric-only over concentric-only training, and only 4 effect sizes (6%) favoured concentric-only training. Both eccentric-only and concentric-only strength training increased MVC CON similarly (13% and 14%) (Fig. 6 ), and 13 out of 71 effect sizes (18%) favoured eccentric-only training, while 11 effect sizes (15%) showed a better effect of concentric-only training on MVC CON (Fig. 4 ). Additionally, both eccentric-only and concentric-only training increased MVC ISO similarity (18% and 17%, respectively) (Fig. 5 ), and 5 out of 20 effect sizes (25%) favoured eccentric-only training and 3 effect sizes (15%) favoured concentric-only training. These meta-analysis results were in line with some original studies investigating the specificity of contraction mode strength gains [ 32 , 43 , 44 ], suggesting that eccentric strength training is superior for improving MVC ECC [ 7 ] and neither concentric nor eccentric training is superior to the other in improving MVC ISO . Although Morrissey et al. [ 7 ] reported that concentric training is preferable for increasing MVC CON, this was not supported by the present study showing that maximal eccentric-only isokinetic training was as equally effective as maximal concentric-only isokinetic strength training for MVC CON strength gains. Mechanisms underpinning increases in muscle strength are stemmed from a combination of neural and morphological factors including enhanced muscle activation through increased muscle motor unit (MU) recruitment, discharge rate, and synchronization, along with an increase in muscle cross-sectional area, changes in muscle architecture, and an increase in musculotendinous stiffness [ 10 ]. These factors could contribute to the strength increases after both eccentric-only and concentric-only training. However, it is possible that some unique adaptations could explain the superiority of maximal eccentric-only to concentric-only training on MVC ECC . Strength gains in the initial several weeks of training are primarily driven by neural adaptations [ 4 , 6 ]. High mechanical forces in eccentric-only training induce unique neural adaptations that are more pronounced [ 14 , 43 ] than those observed in concentric-only training, where the forces are lower [ 8 ]. High mechanical forces during eccentric-only training also lead to a reduction in protective inhibitory peripheral afferent sensory mechanisms, which limit force generation in the muscle-tendon unit [ 45 ]. Downregulation of spinal inhibition, presumably guided by Renshaw cell activity [ 46 ], is regulated by central descending pathways and has been observed in previous studies [ 4 , 10 , 15 , 44 – 46 ]. This is evidenced by the proportionally greater improvement of MU discharge rate after eccentric-only than concentric-only training [ 43 ]. Downregulation of spinal inhibition is also evident after maximal concentric training [ 45 ]; however, this may be more significant after maximal eccentric training, which plays a more critical role in increasing MVC ECC due to the more pronounced protective mechanisms during the initial stages of exercise, attributable to higher mechanical demands [ 9 , 50 ]. This could also be due to lower voluntary activation during eccentric contractions, commonly found in resistance training studies involving participants naive to eccentric training [ 51 , 52 ]. Regarding muscle morphological factors, it is possible that not only contractile muscle structures but also noncontractile structures such as tendon play a role in the greater increases in MVC ECC following eccentric-only than concentric-only training. It has been documented that mechanical tension, exercise-induced muscle damage, and metabolic stress mediate the hypertrophic signalling response to training [ 53 ]. Eccentric-only training may provide higher mechanical stress to induce greater protein signalling cascades and acute inflammatory responses to muscle damage, which are thought to upregulate protein synthesis more effectively when compared with concentric-only training [ 53 , 54 ]. In contrast to concentric contractions, EMG activity does not change with increasing muscle-tendon force in eccentric contractions [ 55 ], indicating that noncontractile elements significantly contribute to force production [ 9 , 56 ]. Noncontractile protein such as titin, connective tissue surrounding muscle fibers and fascicles (i.e., extracellular matrix: ECM) are stretched during the lengthening of the muscle-tendon unit [ 57 ]. This stretching induces adaptations in the connective tissue structures over time, increasing their ability to resist tensile forces and improve sarcomere integrity during eccentric contraction [ 58 ]. The role of titin in force production during eccentric, but less in concentric or isometric contraction has been documented [ 58 – 62 ]. Titin molecules differ between fiber types, being larger and stiffer in type II than in type I [ 59 ]. While they also act as mediators for hypertrophic signalling [ 58 ], this may explain beneficial effect of eccentric training on type II fibers [ 56 ] and muscle hypertrophy [ 63 , 64 ]. The time course of muscle-tendon morphological adaptations is longer than that of neural adaptations [ 47 , 65 – 68 ], thus the beneficial effects of eccentric-only training over concentric-only training on the structural components of the muscle-tendon unit, may take longer to be observed. This speculation aligns with the results of our meta-regression, which showed that the superiority of eccentric-only training for MVC ECC improvement was more pronounced in the studies with longer training durations [ 69 – 73 ] (please also see Table S4 in ESM). Previous studies have also suggested that a longer recovery time after eccentric than concentric training due to muscle damage may be related to the longer time taken for neuromuscular adaptations to be observed after eccentric training [ 10 , 74 ]. In contract, the present study showed no significant difference between eccentric-only and concentric-only strength training for changes in MVC CON and MVC ISO (Fig. 6 ). It could be speculated that the neural and morphological adaptations mentioned above are not specific to eccentric-only training. It may be that the adaptations are also induced by concentric-only training, which induced similar increases in MVC CON and MVC ISO increases after training (Fig. 6 ). Since neural and morphological adaptations for strength gains could be greater after eccentric-only than concentric-only training as discussed above, it seems reasonable to assume that eccentric-only training could also increase MVC CON and MVC ISO greater than concentric-only training, but this was not found. An extra excitatory descending drive to compensate for spinal inhibition (recurrent inhibition and Ib afferent inhibition) may increase through the activation of different cortical areas in eccentric versus concentric contractions [ 75 , 76 ]. Nevertheless, the factors contributing to the modulation of voluntary activation at spinal and supraspinal levels remain unknown [ 77 ]. It has been reported that hypertrophic responses to eccentric versus concentric contractions are achieved through different adaptations in muscle architecture [ 11 ]. Eccentric training results in a significantly greater increase in fascicle length, while concentric training promotes greater changes in pennation angle, likely reflecting the differential addition of sarcomeres either in series or in parallel, respectively [ 11 , 78 ]. Increased muscle cross-sectional area due to eccentric training has been associated with increased fascicle length rather than changes in pennation angle [ 79 – 81 ]. Thus, while both training modes result in more contractile material placed in parallel, predisposing to greater MVC muscle force production in all contraction modes, it may be that changes in fascicle length after eccentric-only training are associated with increases in muscle shortening speed and force production during high-speed dynamic contractions. It is interesting to investigate whether eccentric-only training can increase muscle power and rate of force development better than concentric-only training. It has been shown that an increase in MVC CON is specific to the velocity used in concentric training [ 7 ]. The results of subgroup analyses in the present study indicate that higher-velocity concentric-only training was more effective for improving slower MVC CON when compared to higher-velocity isokinetic eccentric-only training (Table S5 in ESM). This finding contrasts with the finding of a previous study showing that eccentric training with contractions lasting for 2–6 seconds increased concentric 1-RM similarly [ 82 ]. Furthermore, previous studies indicated that fast eccentric training increased muscle thickness [ 64 ] and IIb fiber composition [ 56 ]. This could theoretically benefit increases in MVC CON and MVC ISO , regardless of the movement velocity. Conversely, by increasing the velocity of eccentric contractions, the muscle-tendon force-generating capacity may rely more on noncontractile structures [ 9 , 50 , 51 , 78 ]. This could lead to more favourable adaptations in noncontractile than contractile elements, which might explain why faster eccentric-only training does not necessary increase MVC CON and MVC ISO greater than concentric-only training. It is interesting to investigate further what determines specificity and non-specificity of resistance training with different contraction modes. 4.2 Strengths and limitations This review with meta-analyses was conducted rigorously, with a priori specifications for all criteria. A major strength of our analyses was the high number of included studies and outcomes and comparisons, which enhances the robustness of the results. We also adhered to the recommendations by Kadlec et al. [ 84 ] to further improve the result quality. Additionally, performing sensitivity analyses provided us with insights into the influence of outliers and smaller studies on the overall effects. However, the findings of this review should be interpreted with some limitations, which in turn offer useful guidance for future research. Quality of the study results was very-low to low due to high between-study inconsistency, wide confidence intervals and publication bias. Although we attempted to explore the causes of the heterogeneity by performing subgroup analyses and meta-regressions, we could only explain variability with one moderator for each of MVC ECC and MVC CON improvements. Moreover, a small number of studies were eligible for inclusion in some subgroups (for example, only one study included trained participants) (Tables 2 and 3 ; Tables S4-6 in ESM), and continuous moderator values were homogeneous across the studies (for example, age ranged from 20 to 38), similar to problems identified in previous studies in the field [ 5 ]. It is also important to note that some of the subgroups analysed included fewer than the suggested eight effect sizes [ 85 ] what increases the risk of overfitting. Moreover, moderator variables were not reported in all studies (Tables S4-6 in ESM). Therefore, more studies are required in the future to detail the variability of the results. This is particularly true for MVC ISO , where no moderator could explain the variability of the effects from our study. As shown in Fig. 6 , concentric-only training increased MVC ISO by 17%, followed by MVC CON at 14%, and MVC ECC at 10%. The comparison between training mode specific (i.e., MVC CON ) and non-specific (i.e., MVC ISO ) gains should be interpreted with caution, as a lower number of studies were eligible to be included in the MVC ISO analysis than in the MVC CON and MVC ECC . Readers should also be cautious about generalising the findings of this review. Results are the most generalizable to single-joint exercises and maximal eccentric/concentric-only training using an isokinetic dynamometer, which might be less applicable in practice. Nevertheless, previous review showed that specific strength gains could be similar and even more pronounced when training was performed with isotonic than isokinetic modality [ 25 ]. Therefore, future studies are required to quantify the modality-specificity of the strength gains. Our results are most generalizable to healthy, middle-aged, moderately trained individuals naive to eccentric training, while only one study included strength-trained athletes. 4.3 Practical implications and future research Both eccentric and concentric muscle contractions are included in majority of human movements. Therefore, it is crucial to consider the specific mechanisms associated with each type of contraction independently and in combination. For the maintenance or improvement of health and quality of life related to muscle strength and mass [ 2 ] eccentric contractions should be emphasized during resistance exercise training due to more versatile strength improvements by eccentric training. Moreover, MVC ECC predisposes individuals to better stretch-shortening cycle performance [ 25 ], particularly evident in changes of direction [ 86 ] and jumping performance [ 87 , 88 ]. Eccentric training has proven superior to concentric training for improving the stiffness of elastic elements [ 10 ] and the recoil of elastic energy [ 25 ]. Thus, the present study results recommend the use of maximal eccentric training as the preferred method to increase MVC ECC and consequently enhance performance, while the potential of concentric training for improving MVC ECC is limited. The present study results indicate that the transfer of strength gain from fast maximal eccentric-only training to slow concentric strength is limited; therefore, fast eccentric contractions may not be ideal for improving slow MVC CON . Additionally, as the superiority of eccentric-only to concentric-only training for improving MVC ECC increases over time, strength and conditioning coaches should plan a longer training period to maximize neuromuscular adaptations and performance enhancements [ 10 , 74 ]. Performance testing in research settings should be conducted at later stages post-training protocol to obtain credible insights into the underlying mechanisms or adaptations. Future research should also involve more trained participants and extend over longer periods to ensure comprehensive results. Furthermore, given the higher within-set fatigue tolerance and possible muscle damage specific to eccentric contractions, the dose-response relationships of eccentric training protocols for maximizing strength gains and minimizing the overtraining effect [ 10 , 56 , 74 ] should be carefully considered in future research. This aspect was overlooked in the studies included in our review, with none reporting the conduct of familiarization protocols despite the maximal training intensity expected to cause severe muscle damage [ 89 , 90 ] which can result in suppressed force production and suboptimal training intensity [ 91 , 92 ]; potentially limiting strength gains in the early stages of training. Eccentric exercise-mode specificity of MVC ECC gain [ 5 , 7 ] was confirmed by the results of the present study. Nevertheless, further randomized controlled studies are necessary to elucidate the mechanisms underlying the variability of the effects and to assess the applicability of the results to diverse populations, including young and elderly individuals, across various training modalities, and in the context of more complex, multi-joint human movements. 5 Conclusions The present review with meta-analysis demonstrates the superiority of isokinetic eccentric-only training over concentric-only training in improving MVC ECC . Furthermore, the results indicate a higher transfer effect between training modes with eccentric-only training, while its effects on MVC CON and MVC ISO were similar to those of concentric-only training. It is important to note that the effect of eccentric-only training on MVC CON is greater than the effect of concentric-only training on MVC ECC , and the magnitude of increase in MVC ISO is greater for eccentric-only than concentric-only training. This suggests that eccentric-only training is more versatile than concentric-only training. It seems that despite the unique neural control and muscle-force generating mechanisms involved, eccentric-only strength training leads to adaptations over time that better predispose the muscles' overall force-generating capacities compared to concentric-only strength training. Therefore, the use of eccentric training should be actively promoted in strength and conditioning practice. Declarations Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Availability of data and material: All data generated or analysed during this study are included in the article and its Supplementary files. Competing interests: The authors declare that they have no conflicts of interest relevant to the content of this review. Funding: The Slovenian Research Agency's program 'Kinesiology of Monostructural, Polystructural, and Conventional Sports (P5-0147)' provided partial salary support for DS. Additionally, DS received financial support for a visiting professorship at the Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University in Australia for three months, through the '[RSF] Internal Call for Co-Financing Mobility of Assistants, Assistants with Doctorates, and Higher Education Teachers (Educational Staff) at Higher Education Institutions Abroad for 2023-2024 (B.II.3)' from the University of Ljubljana, Slovenia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Author contributions: DS performed the analyses, visualized the data, and wrote the first draft of the manuscript. DS and KN contributed equally to the conception and design of the study, interpretation of the data, drafting and critical revision of the manuscript. All authors read and approved the final manuscript. Acknowledgements: The authors would like to thank Renan Vieira Barreto for his valuable comments during the preparation of this manuscript. The authors acknowledge the funding bodies to make this collaborative study possible. References Suchomel TJ, Nimphius S, Stone MH. The importance of muscular strength in athletic performance. Sport Med. 2016;46(10):1419–49. https://doi.org/10.1007/s40279-016-0486-0 . Abou Sawan S, Nunes EA, Lim C, McKendry J, Phillips SM. The health benefits of resistance exercise: beyond hypertrophy and big weights. Exerc Sport Mov. 2023;1(1):e00002. https://doi.org/10.1249/ESM.0000000000000001 . Suchomel TJ, Nimphius S, Bellon CR, Stone MH. The importance of muscular strength: training considerations. Sport Med. 2018;48(4):765–85. https://doi.org/10.1007/s40279-018-0862-z . Hedayatpour N, Falla D. Physiological and neural adaptations to eccentric exercise: mechanisms and considerations for training. Biomed Res Int. 2015. https://doi.org/10.1155/2015/193741 . Roig M, O’Brien K, Kirk G, Murray R, McKinnon P, Shadgan B, Reid WD. The effects of eccentric versus concentric resistance training on muscle strength and mass in healthy adults: A systematic review with meta-analysis. Br J Sports Med. 2009;43(8):556–68. https://doi.org/10.1136/bjsm.2008.051417 . Gabriel DA, Kamen G, Frost G. Neural Adaptations to Resistive Exercise. Sport Med. 2006;36(2):133–49. https://doi.org/10.2165/00007256-200636020-00004 . Morrissey MC, Harman EA, Johnson MJ. Resistance training modes:Specificity and effectiveness. Med Sci Sport Exerc. 1995;27(5):648–60. https://doi.org/10.1249/00005768-199505000-00006 . Nuzzo JL, Pinto MD, Nosaka K, Steele J. The eccentric:concentric strength ratio of human skeletal muscle in vivo: Meta-analysis of the influences of sex, age, joint action, and velocity. Sport Med. 2023. https://doi.org/10.1007/s40279-023-01851-y . Douglas J, Pearson S, Ross A, McGuigan M. Eccentric exercise: physiological characteristics and acute responses. Sport Med. 2017;47(4):663–75. https://doi.org/10.1007/s40279-016-0624-8 . Douglas J, Pearson S, Ross A, McGuigan M. Chronic adaptations to eccentric training: A systematic review. Sport Med. 2017;47(5):917–41. https://doi.org/10.1007/s40279-016-0628-4 . Franchi M, Reeves N, Narici M. Skeletal muscle remodeling in response to eccentric vs. concentric loading: Morphological, molecular, and metabolic adaptations. Front Physiol. 2017;8(447):1–16. https://doi.org/10.3389/fphys.2017.00447 . Toigo M, Boutellier U. New fundamental resistance exercise determinants of molecular and cellular muscle adaptations. Eur J Appl Physiol. 2006;97(6):643–63. https://doi.org/10.1007/s00421-006-0238-1 . Malliaras P, Kamal B, Nowell A, Farley T, Dhamu H, Simpson V, Morrissey D, Langberg H, Maffulli N, Reeves ND. Patellar tendon adaptation in relation to load-intensity and contraction type. J Biomech. 2013;46(11):1893–9. https://doi.org/10.1016/j.jbiomech.2013.04.022 . Maeo S, Shan X, Otsuka S, Kanehisa H, Kawakami Y. Neuromuscular adaptations to work-matched maximal eccentric versus concentric training. Med Sci Sports Exerc. 2018;50(8):1629–40. https://doi.org/10.1249/MSS.0000000000001611 . Duclay J, Martin A, Robbe A, Pousson M. Spinal reflex plasticity during maximal dynamic contractions after eccentric training. Med Sci Sports Exerc. 2008;40(4):722–34. https://doi.org/10.1249/MSS.0b013e31816184dc . Higbie EJ, Cureton KJ, Warren GL, Prior BM. Effects of concentric and eccentric training on muscle strength, cross-sectional area, and neural activation. J Appl Physiol. 1996;81(5):2173–81. https://doi.org/10.1152/jappl.1996.81.5.2173 . Nuzzo JL, Pinto MD, Nosaka K. Connective adaptive resistance exercise (CARE) machines for accentuated eccentric and eccentric–only exercise: introduction to an emerging concept. Sport Med. 2023. https://doi.org/10.1007/s40279-023-01842-z . Franchi MV, Maffiuletti NA. Distinct modalities of eccentric exercise: Different recipes, not the same dish. J Appl Physiol. 2019;127(3):881–3. https://doi.org/10.1152/japplphysiol.00093.2019 . Wilk M, Zajac A, Tufano JJ. The influence of movement tempo during resistance training on muscular strength and hypertrophy responses: A review. Sport Med. 2021;51(8):1629–50. https://doi.org/10.1007/s40279-021-01465-2 . Stone MH, Hornsby WG, Suarez DG, Duca M, Pierce KC. Training Specificity for Athletes: Emphasis on Strength-Power Training: A Narrative Review. J Funct Morphol Kinesiol. 2022;7(4). https://doi.org/10.3390/jfmk7040102 . Gault ML, Willems MET. Aging, functional capacity and eccentric exercise training. Aging Dis. 2013;4(6):351–63. https://doi.org/10.14336/AD.2013.0400351 . Mangine GT, Gonzalez AM, Townsend JR, Wells AJ, Beyer KS, Miramonti AA, Ratamess NA, Stout JR, Hoffman JR. Influence of baseline muscle strength and size measures on training adaptations in resistance-trained men. Int J Exerc Sci. 2018;11(4):198–213. Yoshida R, Kasahara K, Murakami Y, Sato S, Nosaka K, Nakamura M. Less fatiguability in eccentric than concentric repetitive maximal muscle contractions. Eur J Appl Physiol. 2023;123(7):1553–65. https://doi.org/10.1007/s00421-023-05178-4 . Schoenfeld BJ, Ogborn DI, Vigotsky AD, Franchi MV, Krieger JW. Hypertrophic effects of concentric vs. eccentric muscle actions. J Strength Cond Res. 2017;31(9):2599–608. https://doi.org/10.1519/JSC.0000000000001983 . Vogt M, Hoppeler HH. Eccentric exercise: Mechanisms and effects when used as training regime or training adjunct. J Appl Physiol. 2014;116(11):1446–54. https://doi.org/10.1152/japplphysiol.00146.2013 . Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE, Chou R, Glanville J, Grimshaw JM, Hróbjartsson A, Lalu MM, Li T, Loder EW, Mayo-Wilson E, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. J Clin Epidemiol. 2022. https://doi.org/10.1016/j.jclinepi.2021.03.001 . Cole V, Boutet M. ResearchRabbit (product review). J Can Heal Libr Assoc. 2023;44(2):43–7. https://doi.org/10.29173/jchla29699 . Greenhalgh T, Peacock R. Effectiveness and efficiency of search methods in systematic reviews of complex evidence: Audit of primary sources. Br Med J. 2005;331(7524):1064–5. https://doi.org/10.1136/bmj.38636.593461.68 . Weir JP, Housh TJ, Weir LL. Electromyographic evaluation of joint angle specificity and cross-training after isometric training. J Appl Physiol. 1994;77(1):197–201. https://doi.org/10.1152/jappl.1994.77.1.197 . Lanza MB, Balshaw TG, Folland JP. Is the joint-angle specificity of isometric resistance training real? And if so, does it have a neural basis? Eur J Appl Physiol. 2019;119(11–12):2465–76. https://doi.org/10.1007/s00421-019-04229-z . Borenstein M, Hedges L, Higgins J, Rothstein H. Introduction to Meta-Analysis. Chichester, UK: Wiley; 2009. https://doi.org/epdf/10.1002/9780470743386 . Hortobagyi T, Devita P, Money J, Barrier J. Effects of standard and eccentric overload strength training in young women. Med Sci Sports Exerc. 2001;33(7):1206–12. https://doi.org/10.1097/00005768-200107000-00020 . Paci M, Bianchini C, Baccini M. Reliability of the PEDro scale: comparison between trials published in predatory and non-predatory journals. Arch Physiother. 2022;12(1):1–9. https://doi.org/10.1186/s40945-022-00133-6 . Hoffmann TC, Glasziou PP, Boutron I, Milne R, Perera R, Moher D, Altman DG, Barbour V, Macdonald H, Johnston M, Kadoorie SEL, Dixon-Woods M, McCulloch P, Wyatt JC, Phelan AWC, Michie S. Better reporting of interventions: Template for intervention description and replication (TIDieR) checklist and guide. BMJ. 2014. https://doi.org/10.1136/bmj.g1687 . Guyatt G, Oxman AD, Akl EA, Kunz R, Vist G, Brozek J, Norris S, Falck-Ytter Y, Glasziou P, Debeer H, Jaeschke R, Rind D, Meerpohl J, Dahm P, Schünemann HJ. GRADE guidelines: 1. Introduction - GRADE evidence profiles and summary of findings tables. J Clin Epidemiol. 2011;64(4):383–94. https://doi.org/10.1016/j.jclinepi.2010.04.026 . Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, Schünemann HJ. GRADE: An emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008;336(7650):924–6. https://doi.org/10.1136/bmj.39489.470347.AD . Guyatt GH, Oxman AD, Kunz R, Brozek J, Alonso-Coello P, Rind D, Devereaux PJ, Montori VM, Freyschuss B, Vist G, Jaeschke R, Williams JW, Murad MH, Sinclair D, Falck-Ytter Y, Meerpohl J, Whittington C, Thorlund K, et al. GRADE guidelines 6. Rating the quality of evidence - Imprecision. J Clin Epidemiol. 2011;64(12):1283–93. https://doi.org/10.1016/j.jclinepi.2011.01.012 . Pustejovsky JE, Tipton E. Meta-analysis with robust variance estimation: expanding the range of working models. Prev Sci. 2022;23(3):425–38. https://doi.org/10.1007/s11121-021-01246-3 . Moeyaert M, Ugille M, Beretvas N, Ferron J, Bunuan R, Van den Noortgate W. Methods for dealing with multiple outcomes in meta-analysis: a comparison between averaging effect sizes, robust variance estimation and multilevel meta-analysis. Int J Soc Res Methodol. 2017;20(6):559–72. https://doi.org/10.1080/13645579.2016.1252189 . Hopkins W, Marshall S, Batterham A, Hanin J. Progressive statistics for studies in sports medicine and exercise science. Med Sci Sport Exerc. 2009;41(1):3–13. https://doi.org/10.1249/MSS.0b013e31818cb278 . Higgins JPT, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. Br Med J. 2003;327(7414):557–60. https://doi.org/10.1136/bmj.327.7414.557 . Ouzzani M, Hammady H, Fedorowicz Z, Elmagarmid A. Rayyan-a web and mobile app for systematic reviews. Syst Rev. 2016;5(1):1–11. https://doi.org/10.1186/s13643-016-0384-4 . Hortobágyi T, Hill JP, Houmard JA, Fraser DD, Lambert NJ, Israel RG. Adaptive responses to muscle lengthening and shortening in humans. J Appl Physiol. 1996;80(3):765–72. https://doi.org/10.1152/jappl.1996.80.3.765 . Hortobágyi T, Barrier J, Beard D, Braspennincx J, Koens P, Devita P, Dempsey L, Lambert J. Greater initial adaptations to submaximal muscle lengthening than maximal shortening. J Appl Physiol. 1996;81(4):1677–82. https://doi.org/10.1152/jappl.1996.81.4.1677 . Aagaard P. Training-induced changes in neural function. Exerc Sport Sci Rev. 2003;31(2):61–7. https://doi.org/10.1097/00003677-200304000-00002 . Barrué-Belou S, Marque P, Duclay J. Recurrent inhibition is higher in eccentric compared to isometric and concentric maximal voluntary contractions. Acta Physiol. 2018;223(4). https://doi.org/10.1111/apha.13064 . Sale DG. Neural adaptation to resistance training. Med Sci Sports Exerc. 1988;20(5):135–45. https://doi.org/10.1249/00005768-198810001-00009 . Aagaard P, Simonsen EB, Andersen JL, Magnusson P, Dyhre-Poulsen P. Neural adaptation to resistance training: Changes in evoked V-wave and H-reflex responses. J Appl Physiol. 2002;92(6):2309–18. https://doi.org/10.1152/japplphysiol.01185.2001 . Aagaard P, Simonsen EB, Andersen JL, Magnusson SP, Halkjær-Kristensen J, Dyhre-Poulsen P. Neural inhibition during maximal eccentric and concentric quadriceps contraction: Effects of resistance training. J Appl Physiol. 2000;89(6):2249–57. https://doi.org/10.1152/jappl.2000.89.6.2249 . Aagaard P. Spinal and supraspinal control of motor function during maximal eccentric muscle contraction: Effects of resistance training. J Sport Heal Sci. 2018;7(3):282–93. https://doi.org/10.1016/j.jshs.2018.06.003 . Beltman JGM, Sargeant AJ, Van Mechelen W, De Haan A. Voluntary activation level and muscle fiber recruitment of human quadriceps during lengthening contractions. J Appl Physiol. 2004;97(2):619–26. https://doi.org/10.1152/japplphysiol.01202.2003 . Babault N, Pousson M, Ballay Y, Van Hoecke J. Activation of human quadriceps femoris during isometric, concentric, and eccentric contractions. J Appl Physiol. 2001;91(6):2628–34. https://doi.org/10.1152/jappl.2001.91.6.2628 . Schoenfeld BJ. The mechanisms of muscle hypertrophy and their application to resistance training. J Strength Cond Res. 2010;24(10):2857–72. https://doi.org/10.1519/JSC.0b013e3181e840f3 . Coffey VG, Hawley JA. The molecular bases of training adaptation. Sport Med. 2007;37(9):737–63. https://doi.org/10.2165/00007256-200737090-00001 . Komi PV, Kaneko M, Aura O. EMG activity of the leg extensor muscles with special reference to mechanical efficiency in concentric and eccentric exercise. Int J Sports Med. 1987;8:22–9. https://doi.org/10.1055/s-2008-1025700 . Paddon-Jones D, Leveritt M, Lonergan A, Abernethy P. Adaptation to chronic eccentric exercise in humans: The influence of contraction velocity. Eur J Appl Physiol. 2001;85(5):466–71. https://doi.org/10.1007/s004210100467 . Hyldahl RD, Chen TC, Nosaka K. Mechanisms and mediators of the skeletal muscle repeated bout effect. Exerc Sport Sci Rev. 2017;45(1):24–33. https://doi.org/10.1249/JES.0000000000000095 . Krüger M, Kötter S. Titin, a central mediator for hypertrophic signaling, exercise-induced mechanosignaling and skeletal muscle remodeling. Front Physiol. 2016;7:1–8. https://doi.org/10.3389/fphys.2016.00076 . Prado LG, Makarenko I, Andresen C, Krüger M, Opitz CA, Linke WA. Isoform diversity of giant proteins in relation to passive and active contractile properties of rabbit skeletal muscles. J Gen Physiol. 2005;126(5):461–80. https://doi.org/10.1085/jgp.200509364 . Nishikawa KC, Lindstedt SL, LaStayo PC. Basic science and clinical use of eccentric contractions: History and uncertainties. J Sport Heal Sci. 2018;7(3):265–74. https://doi.org/10.1016/j.jshs.2018.06.002 . Tomalka A. Eccentric muscle contractions: from single muscle fibre to whole muscle mechanics. Pflugers Arch Eur J Physiol. 2023;475(4):421–35. https://doi.org/10.1007/s00424-023-02794-z . Herzog W. Why are muscles strong, and why do they require little energy in eccentric action? J Sport Heal Sci. 2018;7(3):255–64. https://doi.org/10.1016/j.jshs.2018.05.005 . Azevedo PHSM, Oliveira MGD, Schoenfeld BJ. Effect of different eccentric tempos on hypertrophy and strength of the lower limbs. Biol Sport. 2022;39(2):443–9. https://doi.org/10.5114/BIOLSPORT.2022.105335 . Farthing JP, Chilibeck PD. The effects of eccentric and concentric training at different velocities on muscle hypertrophy. Eur J Appl Physiol. 2003;89(6):578–86. https://doi.org/10.1007/s00421-003-0842-2 . Folland JP, Williams AG. The adaptations to strength training: Morphological and neurological contributions to increased strength. Sport Med. 2007;37(2):145–68. https://doi.org/10.2165/00007256-200737020-00004 . Kubo K, Ikebukuro T, Yata H, Tsunoda N, Kanehisa H. Time course of changes in muscle and tendon properties during strength training and detraining. Strength Cond Res. 2010;24(2):322–31. https://doi.org/10.1519/JSC.0b013e3181c865e2 . Hughes DC, Ellefsen S, Baar K. Adaptations to endurance and strength training. Cold Spring Harb Perspect Med. 2018;8(6):1–17. https://doi.org/10.1101/cshperspect.a029769 . Seynnes OR, de Boer M, Narici MV. Early skeletal muscle hypertrophy and architectural changes in response to high-intensity resistance training. J Appl Physiol. 2007;102(1):368–73. https://doi.org/10.1152/japplphysiol.00789.2006 . Hortobagyi T, Dempsey L, Fraser D, Zheng D, Hamilton G, Lambert J, Dohm L. Changes in muscle strength, muscle fibre size and myofibrillar gene expression after immobilization and retraining in humans. J Physiol. 2000;524(1):293–304. https://doi.org/10.1111/j.1469-7793.2000.00293.x . Seger JY, Thorstensson A. Effects of eccentric versus concentric training on thigh muscle strength and EMG. Int J Sports Med. 2005;26(1):45–52. https://doi.org/10.1055/s-2004-817892 . Seger JY, Arvidsson B, Thorstensson A. Specific effects of eccentric and concentric training on muscle strength and morphology in humans. Eur J Appl Physiol Occup Physiol. 1998;79(1):49–57. https://doi.org/10.1007/s004210050472 . Miller LE, Wootten DF, Nickols-Richardson SM, Ramp WK, Steele CR, Cotton JR, Carneal JP, Herbert WG. Isokinetic training increases ulnar bending stiffness and bone mineral in young women. Bone. 2007;41(4):685–9. https://doi.org/10.1016/j.bone.2007.07.004 . Nickols-Richardson SM, Miller LE, Wootten DF, Ramp WK, Herbert WG. Concentric and eccentric isokinetic resistance training similarly increases muscular strength, fat-free soft tissue mass, and specific bone mineral measurements in young women. Osteoporos Int. 2007;18(6):789–96. https://doi.org/10.1007/s00198-006-0305-9 . Leong CH, McDermott WJ, Elmer SJ, Martin JC. Chronic eccentric cycling improves quadriceps muscle structure and maximum cycling power. Int J Sports Med. 2014;35(7):559–65. https://doi.org/10.1055/s-0033-1358471 . Kwon YH, Park JW. Different cortical activation patterns during voluntary eccentric and concentric muscle contractions: An fMRI study. NeuroRehabilitation. 2011;29(3):253–9. https://doi.org/10.3233/NRE-2011-0701 . Fang Y, Siemionow V, Sahgal V, Xiong F, Yue GH. Distinct brain activation patterns for human maximal voluntary eccentric and concentric muscle actions. Brain Res. 2004;1023(2):200–12. https://doi.org/10.1016/j.brainres.2004.07.035 . Duchateau J, Baudry S. Insights into the neural control of eccentric contractions. J Appl Physiol. 2013;116(11):1418–25. https://doi.org/10.1152/japplphysiol.00002.2013 . Nunes JP, Blazevich AJ, Schoenfeld BJ, Kassiano W, Costa BDV, Ribeiro AS, Nakamura M, Nosaka K, Cyrino ES. Determining changes in muscle size and architecture following exercise training: One site does not fit all. J Strength Cond Res. 2024;38(4):787–90. https://doi.org/10.1519/JSC.0000000000004722 . Baroni BM, Geremia JM, Rodrigues R, De Azevedo Franke R, Karamanidis K, Vaz MA. Muscle architecture adaptations to knee extensor eccentric training: Rectus femoris vs. vastus lateralis. Muscle Nerve. 2013;48(4):498–506. https://doi.org/10.1002/mus.23785 . Reeves ND, Maganaris CN, Longo S, Narici MV. Differential adaptations to eccentric versus conventional resistance training in older humans. Exp Physiol. 2009;94(7):825–33. https://doi.org/10.1113/expphysiol.2009.046599 . Benford J, Hughes J, Waldron M, Theis N. Concentric versus eccentric training: Effect on muscle strength, regional morphology, and architecture. Transl Sport Med. 2021;4(1):46–55. https://doi.org/10.1002/tsm2.197 . Handford MJ, Bright TE, Mundy P, Lake J, Theis N, Hughes JD. The need for eccentric speed: A narrative review of the effects of accelerated eccentric actions during resistance-based training. Sport Med. 2022;52(9):2061–83. https://doi.org/10.1007/s40279-022-01686-z . Weidner S, Tomalka A, Rode C, Siebert T. How velocity impacts eccentric force generation of fully activated skinned skeletal muscle fibers in long stretches. J Appl Physiol. 2022;133(1):223–33. https://doi.org/10.1152/japplphysiol.00735.2021 . Kadlec D, Sainani KL, Nimphius S. With great power comes great responsibility: Common errors in meta-analyses and meta-regressions in strength & conditioning research. Sport Med. 2023;53(2):313–25. https://doi.org/10.1007/s40279-022-01766-0 . Jukic I, Castilla AP, Ramos AG, Van Hooren B, McGuigan MR, Helms ER. The Acute and Chronic Effects of Implementing Velocity Loss Thresholds During Resistance Training: A Systematic Review, Meta-Analysis, and Critical Evaluation of the Literature. Sport Med. 2023;53(1):177–214. https://doi.org/10.1007/s40279-022-01754-4 . Chaabene H, Prieske O, Negra Y, Granacher U. Change of Direction Speed: Toward a Strength Training Approach with Accentuated Eccentric Muscle Actions. Sport Med. 2018;48(8):1773–9. https://doi.org/10.1007/s40279-018-0907-3 . Nishiumi D, Nishioka T, Saito H, Kurokawa T, Hirose N. Associations of eccentric force variables during jumping and eccentric lower-limb strength with vertical jump performance: A systematic review. PLoS ONE. 2023;18(8):1–15. https://doi.org/10.1371/journal.pone.0289631 . Bridgeman LA, McGuigan MR, Gill ND, Dulson DK. Relationships between concentric and eccentric strength and countermovement jump performance in resistance trained men. J Strength Cond Res. 2018;32(1):255–60. https://doi.org/10.1519/JSC.0000000000001539 . Nosaka K, Newton M. Difference in the magnitude of muscle damage between maximal and submaximal eccentric loading. J Strength Cond Res. 2002;16(2):202–8. https://doi.org/10.1519/1533-4287 . Friden J, Sjostrom M, Ekblom B. Myofibrillar damage following intense eccentric exercise in man. Int J Sports Med. 1983;4(3):170–6. https://doi.org/10.1055/s-2008-1026030 . English KL, Loehr JA, Lee SMC, Smith SM. Early-phase musculoskeletal adaptations to different levels of eccentric resistance after 8 weeks of lower body training. Eur J Appl Physiol. 2014;114(11):2264–80. https://doi.org/10.1007/s00421-014-2951-5 . Cheung K, Hume PA, Maxwell L. Delayed onset muscle soreness. Sport Med. 2003;33(2):145–64. https://doi.org/10.2165/00007256-200333020-00005 . Akınoğlu B, Paköz B, Yilmaz AE, Shehu SU, Kocahan T. Effect of contraction type at varying angular velocities on isokinetic muscle strength training. J Exerc Rehabil. 2023;19(4):228–36. https://doi.org/10.12965/jer.2346236.118 . Barak Y, Ayalon M, Dvir Z. Transferability of strength gains from limited to full range of motion. Med Sci Sports Exerc. 2004;36(8):1413–20. https://doi.org/10.1249/01.MSS.0000135777.01093.21 . Blazevich AJ, Cannavan D, Coleman DR, Horne S. Influence of concentric and eccentric resistance training on architectural adaptation in human quadriceps muscles. J Appl Physiol. 2007;103(5):1565–75. https://doi.org/10.1152/japplphysiol.00578.2007 . Cadore EL, González-Izal M, Pallarés JG, Rodriguez-Falces J, Häkkinen K, Kraemer WJ, Pinto RS, Izquierdo M. Muscle conduction velocity, strength, neural activity, and morphological changes after eccentric and concentric training. Scand J Med Sci Sport. 2014;24(5):343–52. https://doi.org/10.1111/sms.12186 . Duncan PW, Chandler JM, Cavanaugh DK, Johnson KR, Buehler AG. Mode and speed specificity of eccentric and concentric exercise training. J Orthop Sports Phys Ther. 1989;11(2):70–5. https://doi.org/10.2519/jospt.1989.11.2.70 . Ellenbecker TS, Davies GJ, Rowinski MJ. Concentric versus eccentric isokinetic strengthening of the rotator cuff. Am J Sports Med. 1988;16(1):64–9. https://doi.org/10.1177/036354658801600112 . Farthing JP, Chilibeck PD. The effect of eccentric training at different velocities on cross-education. Eur J Appl Physiol. 2003;89(6):570–7. https://doi.org/10.1007/s00421-003-0841-3 . Hilliard-Robertson PC, Schneider SM, Bishop SL, Guilliams ME. Strength gains following different combined concentric and eccentric exercise regimens. Aviat Sp Environ Med. 2003;74(4):342–7. https://doi.org/10.52082/jssm.2022.200 . Kim SY, Ko JB, Farthing JP, Butcher SJ. Investigation of supraspinatus muscle architecture following concentric and eccentric training. J Sci Med Sport. 2015;18(4):378–82. https://doi.org/10.1016/j.jsams.2014.05.007 . Paschalis V, Nikolaidis MG, Theodorou AA, Panayiotou G, Fatouros IG, Koutedakis Y, Jamurtas AZ. A weekly bout of eccentric exercise is sufficient to induce health-promoting effects. Med Sci Sports Exerc. 2011;43(1):64–73. https://doi.org/10.1249/MSS.0b013e3181e91d90 . Ruas CV, Brown LE, Lima CD, Costa PB, Pinto RS. Effect of three different muscle action training protocols on knee strength ratios and performance. J Strength Cond Res. 2018;32(8):2154–65. https://doi.org/10.1519/jsc.0000000000002134 . Ruas CV, Pinto RS, Haff GG, Lima CD, Brown LE. Effects of Different Combinations of Concentric and Eccentric Resistance Training Programs on Traditional and Alternative Hamstrings-to-Quadriceps Ratios. Sports. 2019;221:1–15. https://doi.org/doi:10.3390/sports7100221 . Miller LE, Pierson LM, Nickols-Richardson SM, Wootten DF, Selmon SE, Ramp WK, Herbert WG. Knee extensor and flexor torque development with concentric and eccentric isokinetic training. Res Q Exerc Sport. 2012;77(1):58–63. https://doi.org/10.1080/02701367.2006.10599332 . Moore DR, Young M, Phillips SM. Similar increases in muscle size and strength in young men after training with maximal shortening or lengthening contractions when matched for total work. Eur J Appl Physiol. 2012;112(4):1587–92. https://doi.org/10.1007/s00421-011-2078-x . Sato S, Yoshida R, Murakoshi F, Sasaki Y, Yahata K, Kasahara K, Nunes JP, Nosaka K, Nakamura M. Comparison between concentric-only, eccentric-only, and concentric–eccentric resistance training of the elbow flexors for their effects on muscle strength and hypertrophy. Eur J Appl Physiol. 2022;122(12):2607–14. https://doi.org/10.1007/s00421-022-05035-w . Sharma KN, Quddus N, Hameed UA, Khan SA, Kumari A, Alghadir AH, Khan M. Mode-specific effects of concentric and eccentric isokinetic training of the hamstring muscle at slow angular velocity on the functional hamstrings-to-quadriceps ratio - a randomized trial. PeerJ. 2022;10. https://doi.org/10.7717/peerj.13842 . Kiyomi Takayanagi O, Yoshimura, Hidetoshu Ihara AN. Velocity and mode specificity of concentric and eccentric strength training in knee flexors and extensors. J Phys Ther Sci. 1995;7:57–63. https://doi.org/doi.org/10.1589/jpts.7.57 . Timmins RG, Ruddy JD, Presland J, Maniar N, Shield AJ, Williams MD, Opar DA. Architectural changes of the biceps femoris long head after concentric or eccentric training. Med Sci Sports Exerc. 2016;48(3):499–508. https://doi.org/10.1249/MSS.0000000000000795 . Tomberlin JP, Basford JR, Schwen EE, Orte PA, Scott SG, Laughman RK, Ilstrup DM. Comparative study of isokinetic eccentric and concentric quadriceps training. J Orthop Sports Phys Ther. 1991;14(1):31–6. https://doi.org/10.2519/jospt.1991.14.1.31 . Tables Table 1 Summary of the studies with quality evaluation and reporting completeness. Study Measures Sample characteristics Muscle groups Training protocol (repetitions, sets, frequency, duration, velocity) Risk of bias a TIDieR b Akinoglu 2023 [93] MVC CON and MVC ECC at 30, 60, 90 120, 150 and 180°/s mean age = 32 Untrained Sex =MF ECC training n = 14 CON training n = 14 Knee extensors, knee flexors 13, 6, 3, 6, Velocity spectrum c (30, 180°/s) low 6 Barak 2004 [94] MVC CON and MVC ECC at 30, 90°/s MVC ISO at 45° knee flexion mean age = 24 Moderately trained Sex = F Velocity 30°/s: ECC training n = 14 CON training n = 13 Velocity 90°/s: ECC training n = 13 CON training n = 14 Knee extensors 10, 4, 3, 6, Velocity 30 or 90°/s low 6 Benford 2021 [81] MVC CON and MVC ECC at 30°/s MVC ISO at 30 and 90° knee flexion mean age = 23 Moderately trained Sex =M ECC training n = 8 CON training n = 8 Knee extensors 8, 4, 2, 5, Velocity 30°/s low 9 Blazevich 2007 [95] MVC CON and MVC ECC at 30°/s mean age = 24 Moderately trained Sex = MF ECC training n = 12 CON training n = 12 Knee extensors 10, 5, 3, 10, Velocity 30°/s low 6 Cadore 2014 [96] MVC CON and MVC ECC at 60°/s MVC ISO at 60° knee flexion mean age = 23 Moderately trained Sex = MF ECC training n = 11 CON training n = 11 Knee extensors 10, 3.5, 2, 6, Velocity 60°/s low 9 Duncan 1989 [97] MVC CON and MVC ECC at 60, 120, 180°/s mean age = 24 Status NR Sex = M ECC training n = 16 CON training n = 14 Knee extensors 10, 1, 3, 6, Velocity 120°/s moderate 6 Ellenbecker 1988 [98] MVC CON and MVC ECC at 60, 180, 210°/s mean age = NR Trained Sex = MF ECC training n = 11 CON training n = 11 Shoulder internal rotators, shoulder external rotators 10, 6, 2, 6, Velocity MT°/s moderate 6 Farthing 2003 [99] MVC CON and MVC ECC collapsed between 30 and 180°/s mean age = 20 Untrained Sex = MF ECC training n = 13 CON training n = 13 Elbow flexors 8, 6, 3, 8, Velocity 30°/s or 180°/s low 8* Higbie 1996 [16] MVC CON and MVC ECC at 60°/s mean age = 20 Moderately trained Sex = F ECC training n = 19 CON training n = 16 Knee extensors 10, 3, 3, 10, Velocity 60°/s low 7 Hilliard-Robertson 2003 [100] MVC CON and MVC ECC at 60°/s mean age = 33 Moderately trained Sex = MF ECC training n = 11 CON training n = 11 Knee extensors 10, 4, 3, 5, Velocity 60°/s low 6 Hortobágyi 1996 [43] MVC CON and MVC ECC at 60°/s MVC ISO at 45° knee flexion mean age = 22 Untrained Sex = M ECC training n = 7 CON training n = 8 Knee extensors 10, 5, 3, 12, Velocity 60°/s low 7 Hortobágyi 2000 [69] MVC CON and MVC ECC at 60°/s MVC ISO at 45° knee flexion mean age = 22 Moderately trained Sex = MF ECC training n = 12 CON training n = 12 Knee extensors 10, 6, 3, 12, Velocity 60°/s moderate 6 Kim 2015 [101] MVC CON and MVC ECC at 60°/s MVC ISO at 60° shoulder abduction mean age = 28 Status NR Sex =MF ECC training n = 7 CON training n = 6 Shoulder abductors 7, 5, 3, 8, Velocity 60°/s low 7 Paschalis 2011 [102] MVC CON and MVC ECC at 60°/s MVC ISO at 90° knee flexion mean age = 21 Moderately trained Sex = F ECC training n = 10 CON training n = 10 Knee extensors 15, 5, 1, 8, Velocity 60°/s low 7 Ruas 2018 [103] MVC CON and MVC ECC at 60°/s MVC ISO at 60° knee flexion mean age = 23 (2 ECC groups and 1 CON group for knee flexors; 2 CON groups and 1 ECC group for knee extensors) Untrained Sex = M ECC training all n = 10 CON training all n = 10 Knee extensors, knee flexors 10, 3, 2, 6, Velocity spectrum d (60, 90, 120, 150, 180, 210 °/s) low 7 Ruas 2019 [104] MVC CON and MVC ECC at 60°/s mean age = 23 (2 ECC groups and 1 CON group for knee flexors; 2 CON groups and 1 ECC group for knee extensors) Untrained Sex = M ECC training all n = 10 CON training all n = 10 Knee extensors, knee flexors 10, 3, 2, 6, Velocity spectrum d (60, 90, 120, 150, 180, 210 °/s) low 6 Miller 2006 [105] MVC CON and MVC ECC at 60°/s mean age = 38 Moderately trained Sex = F ECC training n = 17 CON training n = 21 Knee extensors, knee flexors 6, 4.5, 3, 20, Velocity 60°/s low 8 Miller 2007 [72] MVC CON and MVC ECC at 60°/s mean age = 20 Status NR Sex = F ECC training n = 32 CON training n = 22 Collapsed elbow extensors and flexors 6, 5, 3, 20, Velocity 60°/s low 7 Moore 2012 [106] MVC CON and MVC ECC at 45 and 300°/s MVC ISO at 60° elbow flexion mean age = 22 Moderately trained Sex =M ECC training n = 9 CON training n = 9 Elbow flexors NR, NR, 2, 9, Velocity 45°/s low 8 Nickols-Richardson 2007 [73] MVC CON and MVC ECC at 60°/s mean age = 20 Moderately trained Sex = F ECC training n = 33 CON training n = 37 Collapsed knee extensors, flexors and Collapsed elbow extensors and flexors 6, 4.5, 3, 20, Velocity 60°/s low 8 Sato 2022 [107] MVC CON and MVC ECC at 30 and 180 °/s MVC ISO at 20, 55 and 90° elbow flexion mean age = 22 Moderately trained Sex = MF ECC training n = 13 CON training n = 13 Elbow flexors 1, 1, 5, 4, Velocity 30°/s low 8 Seger 1998 [71] MVC CON and MVC ECC at 30, 90 and 270°/s MVC ISO at 60° knee flexion mean age = 25 Moderately trained Sex = M ECC training n = 10 CON training n = 10 Knee extensors 10, 4, 3, 10, Velocity 90°/s low 6* Seger 2005 [70] MVC CON and MVC ECC at 30, 90, 270°/s mean age = 25 Moderately trained Sex = M ECC training n = 5 CON training n = 5 Knee extensors 10, 4, 3, 10, Velocity 90°/s low 6 Sharma 2022 [108] MVC CON and MVC ECC at 60°/s mean age = 26 Moderately trained Sex = M ECC training n = 15 CON training n = 15 Knee flexors 10, 3, 2, 6, Velocity 60°/s low 10 Takayanagi 1995 [109] MVC CON and MVC ECC at 60, 120, 180, 240°/s mean age = 20 Moderately trained Sex =MF ECC training n = 10 CON training n = 10 Knee extensors, knee flexors 10, 7, 3, 6, Velocity 180°/s low 6 Timmins 2016 [110] MVC CON and MVC ECC at 60 and 180°/s mean age = 22 Moderately trained Sex =M ECC training n = 14 CON training n = 14 Knee flexors 7, 5, 3, 6, Velocity spectrum c (60, 90°/s) low 9* Tomberlin 1991 [111] MVC CON and MVC ECC at 100°/s mean age = 27 Status NR Sex = MF ECC training n = 21 CON training n = 19 Knee extensors 10, 3, 3, 6, Velocity 100°/s low 7 CON Concentric, ECC Eccentric, F Female, ISO Isometric, M Male, MF mixed sex sample, MVC Maximal Voluntary Contraction. NR Not Reported, collapsed indicates the averaged MVC values for two muscle groups as an outcome a The Physiotherapy Evidence Database scale results, assessing risk of bias (grade on the scale to 11) b Template for Intervention Description and Replication completeness (grade on the scale to 11) c, d Refers to training conditions where each set was performed at different velocities ( c ), or the velocity of training contractions changed from low to high or high to low throughout the training period ( d ) * Crossover study design where each participant was randomly assigned to a sequence of eccentric and concentric trainings (including a washout periods) Table 2 Summarized study characteristics comparing changes in maximal voluntary concentric (MVC CON ) and eccentric contraction (MVC ECC ) strength between eccentric and concentric training protocols Subgroup variable Category n studies (outcomes a ) outcomes a (%) Sex Only men 9 (24) 34 Only women 7 (11) 15 Mixed sample 11 (36) 51 Status Untrained 5 (23) 32 Moderately 18 (36) 52 Trained 1 (6) 8 Not reported 4 (6) 8 Muscle lower body All lower body 20 (56) 79 Knee extensors 17 (37) 66 Knee flexors 3 (18) 32 Knee flexors and extensors 1 (1) 2 Muscle upper body All upper body 7 (15) 21 Elbow flexors only 3 (6) 40 Elbow flexors and extensors 2 (2) 13 Shoulder rotators 1 (6) 40 Shoulder abductors 1 (1) 7 Isokinetic training to testing velocity (°/s) Low to high b 8 (10) 14 High to low c 7 (10) 14 The same e 22 (25) 35 Velocity spectrum e 4 (26) 37 a Number of comparisons between eccentric-only and concentric-only training results b Training and testing at same isokinetic velocity c Training at lower velocity than testing d training at higher velocity than testing e Velocity spectrum pyramidal ordering concept training Table 3 Summarized study characteristics comparing changes in maximal voluntary concentric (MVC CON ), eccentric (MVC ECC ) and isometric (MVC ECC ) strength between eccentric and concentric training protocols Subgroup variable Category n studies (outcomes a ) outcomes a (%) Sex Only men 5 (9) 45 Only women 2 (5) 25 Mixed sample 4 (6) 30 Status Untrained 2 (5) 25 Moderately 8 (14) 70 Not reported 1 (1) 5 Muscle lower body All lower body 8 (15) 75 Knee extensors 8 (13) 87 Knee flexors 1 (2) 13 Muscle upper body All upper body 3 (5) 25 Elbow flexors 2 (4) 80 Shoulder abductors 1 (1) 20 Isokinetic training velocity (°/s) 30 3 (7) 35 45 1 (1) 5 60 5 (5) 25 90 2 (3) 15 Velocity spectrum a 1 (4) 20 a Number of comparisons between eccentric-only and concentric-only training results b Velocity spectrum pyramidal ordering concept training Supplementary Files ElectronicSupplementaryMaterialFile1.docx ElectronicSupplementaryMaterialFile2.xlsx Cite Share Download PDF Status: Published Journal Publication published 21 Aug, 2025 Read the published version in Sports Medicine-Open → Version 1 posted Editorial decision: Major Revision 05 Apr, 2025 Reviewers agreed at journal 20 May, 2024 Reviewers invited by journal 20 May, 2024 Editor assigned by journal 08 May, 2024 First submitted to journal 07 May, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4385283","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":304394289,"identity":"633e7cb5-5386-414e-a5f6-d1613b223d85","order_by":0,"name":"Darjan Spudić","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0001-8353-2958","institution":"Faculty of Sport, University of Ljubljana","correspondingAuthor":true,"prefix":"","firstName":"Darjan","middleName":"","lastName":"Spudić","suffix":""},{"id":304394290,"identity":"3feb5812-0db2-4789-8dc2-72f7ef3fff5c","order_by":1,"name":"Kazunori Nosaka","email":"","orcid":"","institution":"Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University","correspondingAuthor":false,"prefix":"","firstName":"Kazunori","middleName":"","lastName":"Nosaka","suffix":""}],"badges":[],"createdAt":"2024-05-07 20:58:00","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4385283/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4385283/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s40798-025-00887-w","type":"published","date":"2025-08-21T16:29:30+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":57722514,"identity":"5d32a364-3d2d-460c-b650-d12cd4da002c","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":65723,"visible":true,"origin":"","legend":"\u003cp\u003eLiterature search flow chart\u003c/p\u003e\n\u003cp\u003e\u003cem\u003en\u003c/em\u003e number of studies\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/a3c7b382c3eb835b3fc285ad.png"},{"id":57722510,"identity":"240006e7-0556-4b96-8120-b3cce80469e2","added_by":"auto","created_at":"2024-06-04 19:08:57","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":34155,"visible":true,"origin":"","legend":"\u003cp\u003ePercentage of studies achieving each Template for Intervention Description and Replication (TIDieR) checklist item\u003c/p\u003e\n\u003cp\u003eThe checklist key components: \u003cem\u003ename\u003c/em\u003ea brief name to easily identify the intervention, \u003cem\u003ewhy\u003c/em\u003e the rationale or theory behind the study, \u003cem\u003ewhat (materials)\u003c/em\u003e detailed descriptions of the materials and procedures, \u003cem\u003ewhat (procedures)\u003c/em\u003e detail descriptions of the intervention procedures, \u003cem\u003ehow\u003c/em\u003e modes of training delivery, \u003cem\u003ewhere\u003c/em\u003ethe setting of the intervention, \u003cem\u003ewhen and how much\u003c/em\u003e the timing and quantity of the intervention delivery, \u003cem\u003ehow well (actual)\u003c/em\u003e reporting the intervention's actual fidelity, \u003cem\u003ewho\u003c/em\u003e descriptions of the qualifications and background of the intervention providers, \u003cem\u003ehow well (planned)\u003c/em\u003e planning the intervention's fidelity, \u003cem\u003etailoring\u003c/em\u003e considerations for the tailoring of the intervention to individual needs, \u003cem\u003emodifications\u003c/em\u003e any modifications made during the study\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/3d7d08fd80b61e80033f3f6f.png"},{"id":57722516,"identity":"e3a3f470-4a5f-48d6-84dc-76e5bb02b838","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":330206,"visible":true,"origin":"","legend":"\u003cp\u003eMeta-analysis results with forest plot for changes in maximal voluntary eccentric contraction (MVC\u003csub\u003eECC\u003c/sub\u003e) strength following eccentric-only versus and concentric-only training\u003c/p\u003e\n\u003cp\u003eStudy characteristics in brackets: muscle trained and tested [\u003cem\u003eKE\u003c/em\u003e knee extensors, \u003cem\u003eKF\u003c/em\u003e knee flexors, \u003cem\u003eEF\u003c/em\u003e elbow flexors, \u003cem\u003eEE\u003c/em\u003e elbow extensors, \u003cem\u003eSER\u003c/em\u003e shoulder external rotarors, \u003cem\u003eSIR\u003c/em\u003e shoulder internal rotators, \u003cem\u003eSABD\u003c/em\u003e shoulder abductors], sex [\u003cem\u003eM\u003c/em\u003e male, \u003cem\u003eF\u003c/em\u003e female, \u003cem\u003eM+F\u003c/em\u003e mixed sample], participants training status [\u003cem\u003eUN\u003c/em\u003e untrained, \u003cem\u003eMO\u003c/em\u003e moderately trained, \u003cem\u003eTR\u003c/em\u003e highly strength trained, \u003cem\u003eNR\u003c/em\u003e not reported], velocity [training velocity – testing velocity, \u003cem\u003eVS\u003c/em\u003e velocity spectrum pyramidal ordering concept training]\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ea\u003c/em\u003e and \u003cem\u003eb\u003c/em\u003e present outcomes from two eccentric isokinetic training groups from the same study\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/0465e3d3446df50707f471a5.png"},{"id":57722513,"identity":"283af9b3-09c7-43aa-9e9c-68d71288d9fc","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":329838,"visible":true,"origin":"","legend":"\u003cp\u003eMeta-analysis results with forest plot for changes in maximal voluntary concentric contraction (MVC\u003csub\u003eCON\u003c/sub\u003e) strength following eccentric-only versus concentric-only training\u003c/p\u003e\n\u003cp\u003eStudy characteristics in brackets: muscle trained and tested [\u003cem\u003eKE\u003c/em\u003e knee extensors, \u003cem\u003eKF\u003c/em\u003e knee flexors, \u003cem\u003eEF\u003c/em\u003e elbow flexors, \u003cem\u003eEE\u003c/em\u003e elbow extensors, \u003cem\u003eSER\u003c/em\u003e shoulder external rotarors, \u003cem\u003eSIR\u003c/em\u003e shoulder internal rotators, \u003cem\u003eSABD\u003c/em\u003e shoulder abductors], sex [\u003cem\u003eM\u003c/em\u003e male, \u003cem\u003eF\u003c/em\u003e female, \u003cem\u003eM+F\u003c/em\u003e mixed sample], participants training status [\u003cem\u003eUN\u003c/em\u003e untrained, \u003cem\u003eMO\u003c/em\u003e moderately trained, \u003cem\u003eTR\u003c/em\u003e highly strength trained, \u003cem\u003eNR\u003c/em\u003e not reported], velocity [training velocity – testing velocity, \u003cem\u003eVS\u003c/em\u003e velocity spectrum pyramidal ordering concept training]\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ea\u003c/em\u003e and \u003cem\u003eb\u003c/em\u003e present outcomes from two eccentric isokinetic training groups from the same study\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/e45acdb0c9b0df70b74aecdb.png"},{"id":57722517,"identity":"1b2055c9-9d8c-44fd-89fb-3a3c5be9bc89","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":103779,"visible":true,"origin":"","legend":"\u003cp\u003eMeta-analysis results with forest plot for changes in maximal voluntary isometric contraction (MVC\u003csub\u003eISO\u003c/sub\u003e) strength following eccentric-only versus concentric-only training\u003c/p\u003e\n\u003cp\u003eStudy characteristics in brackets: muscle trained and tested [\u003cem\u003eKE\u003c/em\u003e knee extensors, \u003cem\u003eKF\u003c/em\u003e knee flexors, \u003cem\u003eEF\u003c/em\u003e elbow flexors, \u003cem\u003eEE\u003c/em\u003e elbow extensors, \u003cem\u003eSER\u003c/em\u003e shoulder external rotarors, \u003cem\u003eSIR\u003c/em\u003e shoulder internal rotators, \u003cem\u003eSABD\u003c/em\u003e shoulder abductors], sex [\u003cem\u003eM\u003c/em\u003e male, \u003cem\u003eF\u003c/em\u003e female, \u003cem\u003eM+F\u003c/em\u003e mixed sample], participants training status [\u003cem\u003eUN\u003c/em\u003e untrained, \u003cem\u003eMO\u003c/em\u003e moderately trained, \u003cem\u003eNR\u003c/em\u003e not reported]), velocity-angle [training velocity – joint angle of strengh assessement, \u003cem\u003eVS\u003c/em\u003e velocity spectrum pyramidal ordering concept training]\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ea\u003c/em\u003e and \u003cem\u003eb\u003c/em\u003e present outcomes from two eccentric isokinetic training groups from the same study\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/ec718241a5441feb996a597c.png"},{"id":57722512,"identity":"ad95b3be-4d42-4e2d-a44c-234b07bf87a1","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":36040,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003e†\u003c/em\u003e significantly (p\u0026lt;0.05) different from MVC\u003csub\u003eCON\u003c/sub\u003e of respective training\u003c/p\u003e\n\u003cp\u003ePercent improvement with 95% robust confidence intervals of maximal voluntary eccentric (MVC\u003csub\u003eECC\u003c/sub\u003e), concentric (MVC\u003csub\u003eCON\u003c/sub\u003e) and isometric contraction (MVC\u003csub\u003eISO\u003c/sub\u003e) strength after eccentric training and concentric training\u003c/p\u003e\n\u003cp\u003e* significant (p\u0026lt;0.05) difference between eccentric training and concentric training\u003c/p\u003e\n\u003cp\u003e# significantly (p\u0026lt;0.05) different from MVC\u003csub\u003eECC\u003c/sub\u003e of respective training\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/354dddf9eb36984fa84f24fd.png"},{"id":89847211,"identity":"6b0c35eb-14ca-422e-a1cd-f652597cf670","added_by":"auto","created_at":"2025-08-25 16:42:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2870208,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/8b7141c5-b1fe-47ed-9b61-03752b296fbf.pdf"},{"id":57722518,"identity":"e255d125-7b14-46a7-90f2-28f7ad4f3c0c","added_by":"auto","created_at":"2024-06-04 19:08:59","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":627986,"visible":true,"origin":"","legend":"","description":"","filename":"ElectronicSupplementaryMaterialFile1.docx","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/972af206af807a7a58f61477.docx"},{"id":57722511,"identity":"0b35b138-0518-4837-83aa-a2e5f5e5af53","added_by":"auto","created_at":"2024-06-04 19:08:58","extension":"xlsx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":44536,"visible":true,"origin":"","legend":"","description":"","filename":"ElectronicSupplementaryMaterialFile2.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-4385283/v1/5b6281b895ddcbc3ef5b5ccd.xlsx"}],"financialInterests":"","formattedTitle":"Systematic review and meta-analysis of eccentric-only versus concentric-only strength training effects on maximal voluntary eccentric, concentric and isometric contraction strength","fulltext":[{"header":"Key Points","content":"\u003cul\u003e\n \u003cli\u003eEccentric-only strength training is more effective than concentric-only strength training for increasing maximal voluntary eccentric contraction strength (27% vs 10%).\u003c/li\u003e\n \u003cli\u003eThe superiority of eccentric-only training for improving maximal voluntary eccentric contraction strength becomes more prominent with longer training periods, but the effect of faster velocity maximal eccentric-only training on slower maximal voluntary concentric contraction strength is limited.\u003c/li\u003e\n \u003cli\u003eEccentric-only and concentric-only strength training similarly increase maximal voluntary concentric and isometric contraction strength, thus eccentric-only training appears to produce more versatile effects than concentric-only training.\u003c/li\u003e\n \u003cli\u003eMaximal eccentric-only training methods should be actively promoted among strength and conditioning practices to effectively enhance eccentric strength and the movements dependent on it.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"1 Introduction","content":"\u003cp\u003eMuscle strength is crucial not only for athletic performance [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] but also for health and quality of life [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Resistance training is the most effective way to increase muscle strength, and its optimal protocols to increase muscle strength more effectively have been investigated [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Since neuromuscular and functional changes induced by resistance training differ in contraction modes [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], it has been a topic of interest [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In resistance exercises, eccentric (lengthening muscle), concentric (shortening muscle), and isometric (static) contractions are used, and all of them increase muscle strength [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. However, it is not necessarily clear how the contraction modes used in a training affect strength gains in different contraction modes after the training [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMaximal voluntary eccentric contraction strength (MVC\u003csub\u003eECC\u003c/sub\u003e) is more than 40% greater than maximal voluntary concentric contraction strength (MVC\u003csub\u003eCON\u003c/sub\u003e) in isokinetic contractions [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This makes eccentric contractions more advantageous than concentric contractions, since it is possible to impose greater mechanical stimulus to muscles by eccentric contractions, producing better effects on peripheral and central adaptations that underpin muscle strength increase [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Resistance exercises with eccentric contractions (i.e., eccentric resistance exercises) appear to activate satellite cells and muscle protein synthesis pathways, resulting in a greater increase in the number of sarcomeres in parallel and in series [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Moreover, during eccentric contractions, passive muscular tension is generated by lengthening the extracellular matrix and titin [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The combined tension from contractile and noncontractile elements strengthens not only the muscle [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] but also noncontractile elements including tendons [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. It appears that most of the strength gains in shorter than eight weeks of eccentric training are more attributable to increased neural drive [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], possibly due to the more robust downregulation of peripheral inhibitory pathways and higher activity of the central nervous system [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] indicated by an increased motor unit discharge rate [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDue to its potent effects and the advent of new technologies [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], eccentric resistance exercises including those consisting of eccentric-only contractions (concentric contractions are performed without load or with a minimal load) are becoming increasingly prevalent in strength training, rehabilitation, and injury prevention programs [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. However, considerable methodological variations exist in the studies comparing the effects of eccentric versus concentric strength training, which makes conclusions regarding the eccentric versus concentric strength training effects challenging [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The variability stems from the specificity of strength measurements such as one-repetition maximum (1-RM) and maximal voluntary contraction force/torque; training modalities (e.g., isokinetic, isoinertial, and isoweight [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]), muscles trained (e.g., upper body, lower body), and training-related variables including number of repetitions per set, sets per session, frequency of training, duration of the training protocols, and exercise tempo or velocity [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Participant characteristics such as age [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], training status, and initial strength [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], also contribute to this variability. Given that eccentric contractions have higher force generation capability and fatigue tolerance [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], optimal loading during the training should consider these characteristics.\u003c/p\u003e \u003cp\u003ePrevious meta-analysis studies have shown favourable effects of eccentric over concentric resistance exercise training on muscle hypertrophy [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Moreover, the meta-analysis study by Roig et al. [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] identified favourable effects of eccentric-only strength training on MVC\u003csub\u003eECC\u003c/sub\u003e, but did not find significant differences between the two in changes in MVC\u003csub\u003eCON\u003c/sub\u003e and maximal voluntary isometric strength (MVC\u003csub\u003eISO\u003c/sub\u003e). They concluded that the better effects of eccentric-only over concentric-only training were produced by maximal but not submaximal contractions performed in the training [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. They also stated that eccentric-only strength training adaptations were more velocity-specific. However, the authors included only two effect sizes in the subgroup analysis of velocity specific adaptations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. As the magnitude of MVC\u003csub\u003eECC\u003c/sub\u003e to MVC\u003csub\u003eCON\u003c/sub\u003e ratio is known to be influenced by factors such as age, muscle groups assessed, testing velocity, and sex [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] and while different training modalities (e.g., isokinetic dynamometry, free weights) were used for training and testing in various studies included in the review, these could have affected the overall heterogeneity of the results. These should be considered to compare eccentric-only and concentric-only resistance training for their effects on muscle strength.\u003c/p\u003e \u003cp\u003eEccentric training has been proposed to improve muscle mechanical function to a greater extent than other contraction modes [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]; however, the quantification of this effect remains unknown. To investigate the effects of the muscle contraction mode on changes in muscle strength, we thought that the most reliable way would be to perform meta-analyses of existing studies in which compared maximal eccentric-only and concentric-only strength training using an isokinetic dynamometer for changes in changes in MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e, and MVC\u003csub\u003eISO\u003c/sub\u003e strength. Therefore, the main aim of the present systematic review and meta-analyses was to examine the hypothesis that eccentric-only strength training would provide superior effects on not only MVC\u003csub\u003eECC\u003c/sub\u003e but also MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e strength when compared with concentric-only strength training. Additionally, changes in MVC\u003csub\u003eCON\u003c/sub\u003e, MVC\u003csub\u003eECC\u003c/sub\u003e, and MVC\u003csub\u003eISO\u003c/sub\u003e strength were compared within eccentric-only and concentric-only maximum isokinetic contraction training groups to evaluate the transferability of the strength training on strength measures in different contraction modes. We hypothesized that eccentric-only strength training would produce greater increases in not only MVC\u003csub\u003eECC\u003c/sub\u003e strength but also MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e strength when compared with concentric-only strength training, thus eccentric-only strength training would produce greater transferable strength effect on different contraction modes.\u003c/p\u003e"},{"header":"2 Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003e2.1 Study design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis systematic review followed the \u0026ldquo;Preferred Reporting Items for Systematic Reviews and Meta-Analyses\u0026rdquo; guidelines [26]. A review protocol was not pre-registered for this review.\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 Search strategy \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo identify all potentially relevant data from the experimental studies, an initial systematic literature searches were conducted between February and March in 2024, with no limitations based on publication date. Searches included the following databases: MEDLINE/PubMed, SPORTDiscus, and Google Scholar. Moreover, we used \u0026ldquo;snowballing\u0026rdquo; strategies (i.e., reference screening from most relevant studies and citation tracking using a scholarly publication discovery tool supported by artificial intelligence, Research Rabbit [27]) as described by Greenhalgh and Peacock [28]. Electronic databases were searched using the combination of the following search terms: (eccentric or lengthening) AND (shortening or concentric) AND (exercise or training) AND (strength or torque or force or isokinetic or isometric or muscle).\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Data extraction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eArticles were screened following a three-stage process: (1) duplicates of articles identified across numerous search databases were removed; (2) article title and abstracts were screened for suitability. Where a definitive decision could not be made at this stage, studies were taken forward for a full study review; and (3) full articles were screened according to the inclusion and exclusion criteria. All of these were done by one of the authors (DS).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e2.4 Eligibility criteria\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudies were considered to be eligible for inclusion according to the PICOS criteria (Participants, Intervention, Comparator, Outcome, and Study design). The articles that used healthy (i.e., the absence of injury or illness) adult (i.e., 18\u0026ndash;64 years) human \u003cem\u003eparticipants\u003c/em\u003e were chosen. Only randomized controlled exercise intervention studies including both eccentric-only (\u003cem\u003eintervention\u003c/em\u003e) and concentric-only strength training protocols (\u003cem\u003ecomparator\u003c/em\u003e) were included. Training and testing were required to be performed on an isokinetic dynamometer. The primary \u003cem\u003eoutcomes\u003c/em\u003e were percentage changes (mean and standard deviation) in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e before and after training. The secondary outcome was percentage change in MVC\u003csub\u003eISO\u003c/sub\u003e, if reported. Only studies with \u003cem\u003erandomized design\u003c/em\u003e and published in peer-reviewed journals were qualified to be included. If the aforementioned criteria were not fulfilled, or if the strength training protocol was not defined appropriately, or if strength measures were taken outside the training joint range of motion area [29,30], they were excluded. Studies from which we could not extract enough information to calculate the effect size and include them in the qualitative data synthesis were also excluded. Data were extracted by one investigator (DS). Consensus or arbitration by a second investigator (KN) was used to settle any disputes [26].\u003c/p\u003e\n\u003cp\u003eIf a study did not report percent changes and standard deviation of the change within both training groups (for example only means and standard deviations for pre- and post-intervention within each group were reported or only raw change with SD was reported), we calculated the percent change and SD of the percent change relative to the baseline raw value within each group. Finally, for papers in which data were presented in figures, muscle strength values were estimated using a graph digitizer (WebPlotDigitizer, https://apps.automeris.io/wpd/).\u003c/p\u003e\n\u003cp\u003eIn accordance with the recommendation for meta-analysis [31], in case of incomplete data, we calculated missing change score SDs (SDchange) from SD values at baseline (SDpre) and postintervention (SDpost) using the following formula: \u0026radic;((SDpre^2/N)+(SDpost^2/N)); where N was the number of participants. In one study only change over time in raw values was reported [32] for training groups and a control group (which did not train). In this case, percent improvement of the eccentric training and concentric training groups were calculated regarding to control group results using the formula ((eccentric or concentric\u0026ndash;control group)/control group)*100.\u003c/p\u003e\n\u003cp\u003eIn addition to main outcomes, the extracted data from papers included study type (randomized controlled trial or cross design randomized controlled trial); sample size (for eccentric and concentric training groups), sex of the participants (male, female, mixed sample); age of the participants (years), training status of the participants (untrained, moderately trained, trained); muscles trained and tested; testing and training isokinetic velocity (\u0026deg;/s); joint angle of strength assessment (only in the case of MVC\u003csub\u003eISO;\u003c/sub\u003e in degrees [\u0026deg;]); number of repetitions per set; number of sets per session; training frequency (number of sessions per week); duration of the training (in weeks) and participants\u0026rsquo; initial MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e [force or torque, not normalized to body mass]. Additionally, initial eccentric to concentric strength ratio was calculated from the initial MVC\u003csub\u003eECC\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e data.\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.5 Methodological quality assessment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Physiotherapy Evidence Database scale (PEDro), TIDieR (Template for Intervention Description and Replication) and, finally, Grading of Recommendations Assessment, Development and Evaluation (GRADE) checklists were used to assess the risk of bias, completeness of intervention descriptions and quality of evidence, respectively. Using the PEDro scale [33], the listed studies\u0026rsquo; methodological quality was evaluated by the investigator (DS). The PEDro scale consists of 11 items designed to assess methodological quality. Studies were categorized as at low risk (\u0026ge; 6 points), moderate risk (4\u0026ndash;5 points), and high risk (\u0026le; 3 points) of bias. The intervention descriptions were evaluated for completeness using the TIDieR checklist [34]. Finally, the GRADE approach was used to evaluate the oveall quality of the evidence [35,36]. Quality assessement was perfomed separately for each meta-analysis (Table S3 of the ESM). High quality of evidence was initially assumed and then downgraded based on the following criteria: a) risk of bias (downgraded by one level if the median PEDro score was indicative of moderate risk (4 or 5 points) or two levels if scoe was indicative of high risk (\u0026lt; 4 points), b) inconsistency, downgraded by one level if the Cochrane Q test for heterogeneity was significant (p\u0026lt;0.05) or total I\u003csup\u003e2\u003c/sup\u003e exceeded 50%; c) indirectness was considered at low risk, because the PICOS criteria were ensured; d) imprecision [37], downgraded by one level if the confidence interval was large and crossed by a small effect size [\u0026minus;0.2 to 0.2] or [\u0026minus;5 to +5%] considering as and important strenght change over time, and d) publication bias, downgraded by one level if Egger\u0026rsquo;s test, assessing the asymmetry in the funnel plot was significant (p\u0026lt;0.10). The level of certainty was considered as high (considerable confidence exists that the true effect is similar to the estimated effect), moderate (true effect is probably close to the estimated effect), low (true effect might be markedly different from the estimated effect), or very low (true effect is probably markedly different from the estimated effect).\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.6 Statistical analyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhile some studies provided multiple outcomes, multilevel random-effects model meta‑analyses with robust variance estimation were preformed to control for dependent effect sizes in a meta-regression models [38,39]. Following the main objective of our research, MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e changes following the eccentric-only and concentric-only training protocols were compared in separate meta-analyses. Standardized mean differences as Hedge\u0026rsquo;s g (effect size corrected for sample size) with 95% CIs between eccentric-only training and concentric-only training protocols were calculated for individual studies and to test for overall effect. The following categories were used to categorize the size of the effects: trivial (\u0026lt;0.20), small (0.21\u0026ndash;0.60), moderate (0.61\u0026ndash;1.20), large (1.21\u0026ndash;2.00), very large (2.01\u0026ndash;4.00), and extremely large (\u0026gt;4.00) [40]. Forest plots were displayed to graphically represent effects of each individual study, the magnitude of overall effect and its direction (favouring eccentric or concentring training).\u003c/p\u003e\n\u003cp\u003eTo aid interpretation of the findings, separate multilevel random-effects model meta‑analyses of single means with robust variance estimation were used to synthesize the percent (%) outcomes from individual studies for improvements of MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e after eccentric-only and concentric-only training protocols. Percent improvements of MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e were additionally compared within the training mode by pairwise meta‑analyses (improvement of MVC\u003csub\u003eECC\u003c/sub\u003e vs. MVC\u003csub\u003eCON\u003c/sub\u003e vs. MVC\u003csub\u003eISO\u003c/sub\u003e, separately for\u003csub\u003e \u003c/sub\u003eeccentric and concentric training, respectively) to observe the effect of mode-specificity of the training.\u003c/p\u003e\n\u003cp\u003ePublication bias was evaluated with observing asymmetry of the funnel plots by calculating the Egger\u0026rsquo;s statistics. A substantial publication bias was regarded when the p-value was less than 0.10. Moreover, heterogeneity was investigated using the Cochrane Q-test (Chi\u003csup\u003e2 \u003c/sup\u003estatistics), \u0026sigma;\u003csup\u003e2\u003c/sup\u003e test (sigma\u003csup\u003e2\u003c/sup\u003e; variance normalized to effect sizes) and the I\u003csup\u003e2\u003c/sup\u003e (relative measure of heterogeneity among studies; %). Values of 25, 50, and 75% for I\u003csup\u003e2\u003c/sup\u003e signified low, moderate, and high statistical heterogeneity [41]. The heterogeneity was additionally partitioned across two levels (i.e., Level 2: within-study and Level 3: between-study heterogeneity).\u003c/p\u003e\n\u003cp\u003eFor all meta-analytic models, influential case diagnostics were performed to identify studies that have a large influence on the overall effect size. Cook\u0026rsquo;s distance, which combines information about both the leverage and outliers\u0026rsquo; impact on the analysis was calculated to identify if particular study effect size had a potential effect on the estimated coefficients. Individual cases were red flagged if Cook\u0026rsquo;s distance\u0026rsquo;s values exceeded more than three times their respective mean. Robustness of each meta-analysis model was checked with sensitivity analysis, excluding red-flagged studies from the analysis.\u003c/p\u003e\n\u003cp\u003eTo explain the variation of the effects, subgroups analyses were performed for categorical variables: \u003cem\u003esex\u003c/em\u003e [male, female, mixed]; \u003cem\u003emuscle trained \u003c/em\u003e[upper body, lower body]; \u003cem\u003etraining status\u003c/em\u003e of the participants [untrained, moderately trained, highly trained] and \u003cem\u003etraining to testing isokinetic velocity \u003c/em\u003e[with four categories: training at lower velocity than the testing, training at higher velocity than the testing, training at the same velocity as the testing and velocity spectrum pyramidal ordering concept training] (please see Table 1 for explanation). Moreover, to explain the variation of the effects by continuous moderator variables random-effects meta-regressions were performed. These moderators were separated into participant-related (\u003cem\u003eage\u003c/em\u003e of the participants, \u003cem\u003einitial\u003c/em\u003e MVC\u003csub\u003eCON\u003c/sub\u003e, \u003cem\u003einitial\u003c/em\u003e MVC\u003csub\u003eECC\u003c/sub\u003e and \u003cem\u003einitial\u003c/em\u003e MVC\u003csub\u003eECC\u003c/sub\u003e/MVC\u003csub\u003eCON\u003c/sub\u003e ratio) and into training-related moderators (number of \u003cem\u003erepetitions\u003c/em\u003e per set, number of \u003cem\u003esets\u003c/em\u003e, number of training \u003cem\u003esessions\u003c/em\u003e per week and \u003cem\u003eduration\u003c/em\u003e of the resistance training protocol in weeks). For training-related moderators, multiple meta-regression was performed to distinguish the effect of each training-related variable on the effect size while holding other training-related variables constant. The estimated proportional reduction in the total variance was computed using the variance accounted for, a pseudo R\u003csup\u003e2\u003c/sup\u003e value (i.e., the amount of heterogeneity accounted for by the moderator(s)).\u003c/p\u003e\n\u003cp\u003eMeta-analyses were performed in the RStudio: Integrated Development Environment for R (v4.3.3.; Posit team [2024], Boston, MA; http://www.posit.co/, accessed in April 2024). The robust variance estimation method was implemented using the clubSandwich package. Sampling variance-covariance matrix was prepared with estimating 0.6 degree of correlation between sample variances of different outcomes within a study. The matrix was then included into the metaphor package. Moreover, confidence intervals of robust meta-analyses were obtained by adjusting for small samples. The cut-off for statistical significance was set at p \u0026lt; 0.05 [40].\u003c/p\u003e"},{"header":"3 RESULTS","content":"\u003cp\u003e\u003cstrong\u003e3.1 Search results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe initial search yielded 6,614 studies, and we observed that using different search terms to narrow them could overlook some of the of the most relevant research. Therefore, we adopted a more conservative approach. Identified records were filtered using keywords in titles and abstracts through the systematic review software Rayyan [42] (https://www.rayyan.ai/, accessed in March 2024). Additionally, reference screening was performed on the most relevant studies, and citation tracking was conducted using Research Rabbit software [27] (https://www.researchrabbit.ai/, accessed in March 2024), which yielded an additional 50 potentially useful studies. Our systematic review and meta-analysis ultimately included 27 studies. Of these, 11 studies reported changes in all three strength measures (MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e, and MVC\u003csub\u003eISO\u003c/sub\u003e) following both concentric-only and eccentric-only training. However, 16 studies did not report changes in MVC\u003csub\u003eISO\u003c/sub\u003e. In total, we gathered 162 study results (expressed as changes in percent units). This enabled us to calculate 71 standardized effect sizes for differences in improvements of MVC\u003csub\u003eECC\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e between both training groups (71 results in each group) and 20 standardized effect sizes for differences in improvements of MVC\u003csub\u003eISO\u0026nbsp;\u003c/sub\u003ebetween training groups (20 results in each group). To aid interpretation of the findings, results of multiple studies within each training group and contraction mode were summarized and compared in separate meta-analyses. The stages of the search and study selection process are presented in Fig. 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 Study characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIndividual study characteristics are presented in Table 1. Summary of study characteristics reporting MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e by categorical subgroup variables are presented in Table 2. The summary of study characteristics by categorical subgroup variables for the studies reporting MVC\u003csub\u003eCON\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e and additionally MVC\u003csub\u003eISO\u003c/sub\u003e are presented in Table 3. Additionally, in studies reporting MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e (Table 2), the number of repetitions per set ranged from 1 to 15 (mode = 10; mean \u0026plusmn; SD = 9.6 \u0026plusmn; 2.4), the number of sets ranged from 1 to 7 (mode = 3; mean \u0026plusmn; SD = 4.7 \u0026plusmn; 1.6), the number of training session per week ranged from 1 to 5 (mode = 3; mean \u0026plusmn; SD = 2.8 \u0026plusmn; 0.6) and training protocol duration ranged from 4 to 20 weeks (mode = 6; mean \u0026plusmn; SD = 7.8 \u0026plusmn; 3.8). The mean age of the participants was 25 years (SD = 4.7; range 20-38). The number of participants was 364 for the eccentric training group and 354 for the concentric training group. When summarizing multiple results from the same studies, the totals were 904 and 899, respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e** Table 1 around here **\u003c/p\u003e\n\u003cp\u003e** Table 2 around here **\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the studies where MVC\u003csub\u003eISO\u003c/sub\u003e was reported (Table 3), the number of repetitions per set ranged from 1 to 15 (mode = 10; mean \u0026plusmn; SD = 9.0 \u0026plusmn; 3.1), the number of sets ranged from 1 to 6 (mode = 3; mean \u0026plusmn; SD = 3.7 \u0026plusmn; 1.2), the number of training session per week ranged from 1 to 5 (mode = 3; mean \u0026plusmn; SD = 2.9 \u0026plusmn; 0.9) and training protocol duration ranged from 4 to 12 weeks (mode = 6; mean \u0026plusmn; SD = 6.4 \u0026plusmn; 2.0). The mean age of the participants was 23.3 years (SD = 1.3; range 21-28). The number of participants was 111 for the eccentric training group and 110 for the concentric training group. When summarizing multiple results from the same studies, the totals were 215 and 215, respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e** Table 3 around here **\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 Quality of evidence and completeness of reporting\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePEDro scale values and completeness of reporting of the controlled randomized study items are presented for each particular study in Table 1. PEDro scores ranged from 5 to 9 (mode = 6; mean \u0026plusmn; SD = 6.3 \u0026plusmn; 1.0) indicating low to moderate risk of bias (Table S1 of the ESM). As shown in Figure 2, all studies reported the execution of the testing and training procedures, but only 19% reported who performed the training or testing protocol, 44% clarified where the training and testing was performed, 15% clarified if sample size was calculated, and 37% of the studies reported information regarding the dropout of the participants. None of the studies reported tailoring and/or modifications of training protocols (Table S2 of the ESM).\u003c/p\u003e\n\u003cp\u003eAltogether, due considerable heterogeneity (Q test results) and publication bias (Egger\u0026rsquo;s statistics; further reported in text following the results of the particular meta-analysis results and summarized in Table S3 of the ESM), quality of evidence were downgraded from high quality to low quality according to GRADE approach\u0026nbsp;[36]\u0026nbsp;for MVC\u003csub\u003eECC\u003c/sub\u003e results. Additionally, due to imprecision (confidence interval was crossed by a small effect size), MVC\u003csub\u003eCON\u003c/sub\u003e and\u003csub\u003e\u0026nbsp;\u003c/sub\u003eMVC\u003csub\u003eISO\u0026nbsp;\u003c/sub\u003eresults were downgraded to very low quality.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4 Meta-analyses results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.1 Effect of different resistance training modes on eccentric strength gain (MVC\u003csub\u003eECC\u003c/sub\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA meta-analysis of 27 studies with 71 comparisons showed statistically significantly beneficial effects of eccentric-only in comparison to concentric-only strength training for improvement of MVC\u003csub\u003eECC\u003c/sub\u003e (Hedge\u0026rsquo;s g = 2.03, 95% CI: 0.74 to 3.32; p \u0026lt; 0.01; very large effect) (Figure S1 of the Electronic Supplementary Material [ESM]). A small sample adjustment to the robust meta-analysis results expanded the confidence intervals of Hedge\u0026rsquo;s to 0.69 to 3.39. Five individual effect sizes from two studies were identified as highly influential. However, the overall results were robust to their exclusion from the model as the interpretation of the model did not change. Overall Hedge\u0026rsquo;s g decreased to 1.51 (95% CI: 0.59 to 2.42; p \u0026lt; 0.01; large effect), with the small sample adjustment for the 95% CI being 0.55 to 2.47 (Fig. 3).\u003c/p\u003e\n\u003cp\u003eEgger\u0026rsquo;s test results indicated publication bias for the MVC\u003csub\u003eECC\u003c/sub\u003e (p\u0026lt;0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 647.9, df = 65; p \u0026lt; 0.01; I\u003csup\u003e2\u003c/sup\u003e = 96.5%). Within study effect size variability (Level 2) was low to moderate (29%), while between study variability (Level 3) was moderate to high (68%).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.2 Effect of resistance training modes on concentric strength gain (MVC\u003csub\u003eCON\u003c/sub\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA meta-analysis of 27 studies with 71 comparisons did not show statistically significantly different benefits of eccentric-only and concentric-only strength training for improvement of MVC\u003csub\u003eCON\u003c/sub\u003e (Hedge\u0026rsquo;s g = \u0026ndash;0.71, 95% CI \u0026ndash;1.65 to 0.22; p = 0.13; small effect) (Figure S2 of the ESM). A small sample adjustment to the robust meta-analysis results expanded the confidence intervals of Hedge\u0026rsquo;s to \u0026ndash;1.69 to 0.27. Five individual effect sizes from three studies were identified as highly influential. However, the overall results were robust to their exclusion from the model as the interpretation of the model did not change. Overall Hedge\u0026rsquo;s g decreased to trivial, i.e. \u0026ndash;0.10 (95% CI: \u0026ndash;0.69 to 0.48) with small sample adjustment 95% CI ranging from \u0026ndash;0.72 to 0.51 (Fig. 4).\u003c/p\u003e\n\u003cp\u003eEgger\u0026rsquo;s test results indicated publication bias for the MVC\u003csub\u003eCON\u003c/sub\u003e (p\u0026lt;0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 358.4, df = 65; p\u0026lt;0.01; I\u003csup\u003e2\u003c/sup\u003e = 92%). Within study effect size variability (Level 2) was low (21%), while between study variability (Level 3) was moderate to high (71%).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.3 Effect of resistance training modes on isometric strength gain (MVC\u003csub\u003eISO\u003c/sub\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA meta-analysis of 11 studies with 20 comparisons did not show statistically significantly different effects between eccentric and concentric resistance training protocols for improvement of MVC\u003csub\u003eISO\u003c/sub\u003e (Hedge\u0026rsquo;s g = \u0026ndash;0.31, 95% CI \u0026ndash;2.40 to 1.75; p = 0.77; small effect) (Figure S3 of the ESM). A small sample adjustment to the robust meta-analysis results expanded the confidence interval (Hedge\u0026rsquo;s g = \u0026ndash;0.31, 95% CI \u0026ndash;2.65 to 2.02). Two individual effect sizes from two studies were identified as highly influential. After removing them from the analysis, the overall effect size changed sign and narrowed the confidence intervals from negative (favouring concentring training) to positive trivial (Hedge\u0026rsquo;s g: 0.04 with 95% CI: \u0026ndash;0.82 to 0.90), favouring eccentric training (Fig. 5). Confidence intervals (95%) for robust meta-analysis with small samples adjustment ranged from \u0026ndash;0.96 to 1.05.\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEgger\u0026rsquo;s test results indicated publication bias for the MVC\u003csub\u003eISO\u003c/sub\u003e (p\u0026lt;0.01) meta-analysis indicating smaller studies showing higher benefits in favour of eccentric or concentric training, respectively. Moreover, statistically significant overall heterogeneity among the studies was found (Q = 120.7, df = 25; p\u0026lt;0.01; I\u003csup\u003e2\u003c/sup\u003e = 89%). Within study effect size variability (Level 2) was low (11%), while between study variability (Level 3) was moderate to high (71%).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.4 Analyses of moderators\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDespite high statistical heterogeneity among the studies comparing the magnitude of increase of MVC\u003csub\u003eECC\u003c/sub\u003e between eccentric and concentric training, no statistically significant differences were found within subgroups of \u003cem\u003esex\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 3.2; p = 0.20; pseudo R\u003csup\u003e2\u003c/sup\u003e = 2.7%), \u003cem\u003emuscle\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.59; p = 0.44; pseudo R\u003csup\u003e2\u003c/sup\u003e = 6%), and \u003cem\u003etraining status\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.89; p = 0.83; pseudo R\u003csup\u003e2\u003c/sup\u003e = 18%). Effect of eccentric-only training was more superior when testing was performed at the same velocity as training in comparison to when testing was performed at the lower velocity as the training (difference of 1.53 in Hedge\u0026rsquo;s g, p\u0026lt;0.05), nevertheless training to testing isokinetic velocity subgroups together could not explain the variability of the effect (Chi\u003csup\u003e2\u003c/sup\u003e = 7.2; p = 0.07; pseudo R\u003csup\u003e2\u003c/sup\u003e = 1%). Participant-related continuous moderators analyses showed no effect of \u003cem\u003eage\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 3.0; p = 0.08; pseudo R\u003csup\u003e2\u003c/sup\u003e = 12.7%), \u003cem\u003einitial MVC\u003csub\u003eECC\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.16; p = 0.69, pseudo R\u003csup\u003e2\u003c/sup\u003e = 10%), \u003cem\u003einitial MVC\u003csub\u003eCON\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.55; p = 0.46, pseudo R\u003csup\u003e2\u003c/sup\u003e = 12%) and \u003cem\u003eMVC\u003csub\u003eECC\u003c/sub\u003e/MVC\u003csub\u003eCON\u003c/sub\u003e ratio\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 2.05; p = 0.15; pseudo R\u003csup\u003e2\u003c/sup\u003e = 12%). Moreover, training related variables included in multiple meta-regression (\u003cem\u003enumber of repetitions\u003c/em\u003e, \u003cem\u003esets\u003c/em\u003e, \u003cem\u003efrequency\u003c/em\u003e and \u003cem\u003eduration of training\u003c/em\u003e), could not statistically significantly explain the variability (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 8.2; p = 0.08; pseudo R\u003csup\u003e2\u003c/sup\u003e =\u003csup\u003e\u0026nbsp;\u003c/sup\u003e19.5%). Within training-related factors, only \u003cem\u003eduration\u003c/em\u003e of the training protocol had shown statistically significant influence to the effect size (\u0026beta; = 0.25 [95% CI: 0.05-0.45]; SE = 0.10; z = 2.4; p \u0026lt; 0.05). Thus, the longer the training protocol, the more beneficial the eccentric training was over concentric training for improving MVC\u003csub\u003eECC\u003c/sub\u003e when controlling for the rest of training-related factors (Table S4 of the ESM).\u003c/p\u003e\n\u003cp\u003eComparing the magnitude of increase of MVC\u003csub\u003eCON\u003c/sub\u003e between eccentric and concentric training, no statistically significant differences were found between subgroups of \u003cem\u003esex\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 3.90; p = 0.14; pseudo R\u003csup\u003e2\u003c/sup\u003e = 4.4%), \u003cem\u003emuscle\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.00; p = 0.98; pseudo R\u003csup\u003e2\u003c/sup\u003e = 10%) and \u003cem\u003etraining status\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 1.89; p = 0.60; pseudo R\u003csup\u003e2\u0026nbsp;\u003c/sup\u003e= 21%). Statistically significant differences were found within subgroups of \u003cem\u003etraining to testing isokinetic velocity\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 8.4; p \u0026lt; 0.05; pseudo R\u003csup\u003e2\u003c/sup\u003e = 49%). A statistically significant lower effect of eccentric training compared to concentric training on the improvement of MVC\u003csub\u003eCON\u003c/sub\u003e was observed when the eccentric training was performed at higher velocities than those used in the MVC\u003csub\u003eCON\u003c/sub\u003e testing in comparison to the effect of the same training and testing velocity (Hedge\u0026rsquo;s g = \u0026ndash;0.99 [95% CI from \u0026ndash;1.75 to \u0026ndash;0.23]; p \u0026lt; 0.05). Participant-related continuous moderators showed no effect of \u003cem\u003eage\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.68; p = 0.41; pseudo R\u003csup\u003e2\u003c/sup\u003e = 13%), \u003cem\u003einitial MVC\u003csub\u003eECC\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.08; p = 0.77; pseudo R\u003csup\u003e2\u0026nbsp;\u003c/sup\u003e= 14.5%), \u003cem\u003einitial MVC\u003csub\u003eCON\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.19; p = 0.66; pseudo R\u003csup\u003e2\u0026nbsp;\u003c/sup\u003e\u0026lt; 19.7%) and \u003cem\u003eMVC\u003csub\u003eECC\u003c/sub\u003e/MVC\u003csub\u003eCON\u003c/sub\u003e ratio\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 1.84; p = 0.17; pseudo R\u003csup\u003e2\u003c/sup\u003e = 5.2%). Moreover, training related variables (\u003cem\u003enumber of repetitions\u003c/em\u003e, \u003cem\u003esets\u003c/em\u003e, \u003cem\u003efrequency\u003c/em\u003e and \u003cem\u003eduration of training\u003c/em\u003e), could not statistically significantly explain the variability (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 5.7; p = 0.22; pseudo R\u003csup\u003e2\u003c/sup\u003e = 40.7 %) (Table S5 of the ESM).\u003c/p\u003e\n\u003cp\u003eAmong the studies comparing the magnitude of increase of MVC\u003csub\u003eISO\u003c/sub\u003e between eccentric and concentric training, no statistically significant differences were found within subgroups of \u003cem\u003esex\u0026nbsp;\u003c/em\u003e(Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.02; p = 0.99; pseudo R\u003csup\u003e2\u003c/sup\u003e = 47%), \u003cem\u003emuscle\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e = 0.20; p = 0.66; pseudo R\u003csup\u003e2\u003c/sup\u003e = 18%) and \u003cem\u003etraining status\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 2.85; p = 0.24; pseudo R\u003csup\u003e2\u003c/sup\u003e = 9%). Participant-related continuous moderators showed no effect of \u003cem\u003eage\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.3; p = 0.60; pseudo R\u003csup\u003e2\u003c/sup\u003e = 14.7%), \u003cem\u003einitial MVC\u003csub\u003eECC\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.10; p = 0.75, pseudo R\u003csup\u003e2\u003c/sup\u003e = 3.6%), \u003cem\u003einitial MVC\u003csub\u003eCON\u003c/sub\u003e\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.5; p = 0.47, pseudo R\u003csup\u003e2\u003c/sup\u003e = 29%) and \u003cem\u003eMVC\u003csub\u003eECC\u003c/sub\u003e/MVC\u003csub\u003eCON\u003c/sub\u003e ratio\u003c/em\u003e (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.17; p = 0.68; pseudo R\u003csup\u003e2\u003c/sup\u003e = 31%). Moreover, training related variables (\u003cem\u003enumber of repetitions\u003c/em\u003e, \u003cem\u003esets\u003c/em\u003e, \u003cem\u003efrequency\u003c/em\u003e and \u003cem\u003eduration of training\u003c/em\u003e), could not statistically significantly explain the variability (Chi\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= 0.65; p = 0.96; pseudo R\u003csup\u003e2\u003c/sup\u003e =\u003csup\u003e\u0026nbsp;\u003c/sup\u003e14%) (Table S6 of the ESM).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.5 Changes in strength within training group\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs shown in Fig. 6, results from individual studies indicate that \u003cem\u003eeccentric-only training\u003c/em\u003e resulted in an improvement of MVC\u003csub\u003eECC\u003c/sub\u003e by 27.3% (95% CI: 19.4-35.2%; p\u0026lt;0.05; robust 95% CI: 18.2-36.4%), MVC\u003csub\u003eCON\u003c/sub\u003e by 12.6% (95% CI: 8.6-16.7%; p\u0026lt;0.05; robust 95% CI: 8.0-17.3%), and MVC\u003csub\u003eISO\u003c/sub\u003e by 18.2% (95% CI: 11.7-24.7%; p\u0026lt;0.05; robust 95% CI: 10.2-26.2%) (Table S7 of the ESM).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eImprovements after \u003cem\u003econcentric-only training\u003c/em\u003e were observed as follows: MVC\u003csub\u003eECC\u003c/sub\u003e increased by 10.2% (95% CI: 8.2-12.3%; p\u0026lt;0.05; robust 95% CI: 7.2-13.2%), MVC\u003csub\u003eCON\u003c/sub\u003e by 13.8% (95% CI: 10.0-17.5%; p\u0026lt;0.05; robust 95% CI: 9.7-17.9%), and MVC\u003csub\u003eISO\u003c/sub\u003e by 16.9% (95% CI: 9.5-24.2%; p\u0026lt;0.05; robust 95% CI: 7.8-25.9%) (Table S7 of the ESM).\u003c/p\u003e\n\u003cp\u003eNo influential individual results were identified, and Egger\u0026rsquo;s test results showed no publication bias, with p-values ranging from 0.08 for MVC\u003csub\u003eCON\u003c/sub\u003e after concentric training to 0.797 for MVC\u003csub\u003eISO\u003c/sub\u003e after eccentric training. Statistically significant heterogeneity was confirmed by Q-test (p\u0026lt;0.05) in all cases, with I\u003csup\u003e2\u003c/sup\u003e values exceeding 98% in all cases. Specifically, level 2 I\u003csup\u003e2\u003c/sup\u003e varied from 0% for MVC\u003csub\u003eISO\u003c/sub\u003e after concentric training to 27% for MVC\u003csub\u003eCON\u003c/sub\u003e after concentric training, while level 3 I\u003csup\u003e2\u003c/sup\u003e ranged from 72% for MVC\u003csub\u003eCON\u003c/sub\u003e after concentric training to 99% for MVC\u003csub\u003eISO\u003c/sub\u003e after concentric training (Table S7 of the ESM).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4.5 Differences in strength changes within training group and between groups\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePairwise comparisons revealed differences in strength improvement among testing contraction modes following \u003cem\u003eeccentric-only training\u003c/em\u003e: MVC\u003csub\u003eECC\u003c/sub\u003e versus MVC\u003csub\u003eCON\u003c/sub\u003e showed an 11.5% difference (95% CI: 11.2-11.7; robust 95% CI: \u0026ndash;1.9 to 24.8; p\u0026lt;0.05), illustrated in Fig. 6. The difference between MVC\u003csub\u003eECC\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e was 8.6% (95% CI: 8.0-9.3; robust 95% CI: \u0026ndash;44.4 to 61.7; p\u0026lt;0.05), and between MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e was 3.8% (95% CI: 3.3-4.3; robust 95% CI: \u0026ndash;5.7 to 13.2; p\u0026lt;0.05) (Table S8 of the ESM).\u003c/p\u003e\n\u003cp\u003eFor \u003cem\u003econcentric-only training\u003c/em\u003e, the respective differences were also notable: MVC\u003csub\u003eECC\u003c/sub\u003e versus MVC\u003csub\u003eCON\u003c/sub\u003e at 1.7% (95% CI: 1.5-1.9; robust 95% CI: 4.1-7.5; p\u0026lt;0.05), MVC\u003csub\u003eECC\u003c/sub\u003e versus MVC\u003csub\u003eISO\u003c/sub\u003e at 6.2% (95% CI: 5.7-6.7; robust 95% CI: 1.4-11.0; p\u0026lt;0.05), and MVC\u003csub\u003eCON\u003c/sub\u003e versus MVC\u003csub\u003eISO\u003c/sub\u003e at 2.1% (95% CI: 1.7-2.6; robust 95% CI: \u0026ndash;7.0 to 11.2; p\u0026lt;0.05) (Table S8 of the ESM).\u003c/p\u003e\n\u003cp\u003eNo influential individual results sizes were detected. Egger\u0026rsquo;s test revealed publication bias (p\u0026lt;0.10) in all comparisons except for MVC\u003csub\u003eECC\u003c/sub\u003e versus MVC\u003csub\u003eISO\u003c/sub\u003e after concentric training (p=0.44), and statistically significant heterogeneity was confirmed in all cases with Q-test\u0026rsquo;s Chi\u003csup\u003e2\u003c/sup\u003e statistics (p\u0026lt;0.05). I\u003csup\u003e2\u003c/sup\u003e values exceeded 90% for all comparisons. Specifically, level 2 (within-study) I\u003csup\u003e2\u003c/sup\u003e ranged from 38.6% for the MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e comparison for concentric training to 66.4% for the MVC\u003csub\u003eECC\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e comparison post concentric training. Level 3 (between-study) I\u003csup\u003e2\u003c/sup\u003e ranged from 32.3% for the MVC\u003csub\u003eECC\u003c/sub\u003e vs MVC\u003csub\u003eISO\u003c/sub\u003e comparison post concentric training to 62% for the MVC\u003csub\u003eECC\u003c/sub\u003e vs MVC\u003csub\u003eCON\u003c/sub\u003e comparison post eccentric training (Table S8 of the ESM).\u003c/p\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eThe present systematic review with meta-analyses examined the hypothesis that eccentric-only strength training would increase not only MVC\u003csub\u003eECC\u003c/sub\u003e but also MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e greater when compared with concentric-only strength training. It was found that both eccentric-only and concentric-only strength training increased MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e, and MVC\u003csub\u003eISO\u003c/sub\u003e. The results of the meta-analyses partially supported the hypothesis such that eccentric-only strength training was better for increasing MVC\u003csub\u003eECC\u003c/sub\u003e, but the increases in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e were not significantly different between eccentric-only and concentric-only strength training. The results also showed that the longer the training period, the greater the increase in MVC\u003csub\u003eECC\u003c/sub\u003e by eccentric-only than concentric-only training. Moreover, higher-velocity eccentric-only training had a lower effect on slower MVC\u003csub\u003eCON\u003c/sub\u003e strength gains when compared with concentric-only higher-velocity training.\u003c/p\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003e4.1 Specificity of strength gain\u003c/h2\u003e \u003cp\u003eWhile both eccentric-only and concentric-only strength training were effective for increasing MVC\u003csub\u003eECC\u003c/sub\u003e, eccentric-only training led to a greater increase (27%) than concentric-only training (10%) as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e. As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, 29 out of 71 individual effect sizes (41%) favoured eccentric-only over concentric-only training, and only 4 effect sizes (6%) favoured concentric-only training. Both eccentric-only and concentric-only strength training increased MVC\u003csub\u003eCON\u003c/sub\u003e similarly (13% and 14%) (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e), and 13 out of 71 effect sizes (18%) favoured eccentric-only training, while 11 effect sizes (15%) showed a better effect of concentric-only training on MVC\u003csub\u003eCON\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Additionally, both eccentric-only and concentric-only training increased MVC\u003csub\u003eISO\u003c/sub\u003e similarity (18% and 17%, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), and 5 out of 20 effect sizes (25%) favoured eccentric-only training and 3 effect sizes (15%) favoured concentric-only training. These meta-analysis results were in line with some original studies investigating the specificity of contraction mode strength gains [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e], suggesting that eccentric strength training is superior for improving MVC\u003csub\u003eECC\u003c/sub\u003e [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] and neither concentric nor eccentric training is superior to the other in improving MVC\u003csub\u003eISO\u003c/sub\u003e. Although Morrissey et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] reported that concentric training is preferable for increasing MVC\u003csub\u003eCON,\u003c/sub\u003e this was not supported by the present study showing that maximal eccentric-only isokinetic training was as equally effective as maximal concentric-only isokinetic strength training for MVC\u003csub\u003eCON\u003c/sub\u003e strength gains.\u003c/p\u003e \u003cp\u003eMechanisms underpinning increases in muscle strength are stemmed from a combination of neural and morphological factors including enhanced muscle activation through increased muscle motor unit (MU) recruitment, discharge rate, and synchronization, along with an increase in muscle cross-sectional area, changes in muscle architecture, and an increase in musculotendinous stiffness [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These factors could contribute to the strength increases after both eccentric-only and concentric-only training. However, it is possible that some unique adaptations could explain the superiority of maximal eccentric-only to concentric-only training on MVC\u003csub\u003eECC\u003c/sub\u003e. Strength gains in the initial several weeks of training are primarily driven by neural adaptations [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. High mechanical forces in eccentric-only training induce unique neural adaptations that are more pronounced [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e] than those observed in concentric-only training, where the forces are lower [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. High mechanical forces during eccentric-only training also lead to a reduction in protective inhibitory peripheral afferent sensory mechanisms, which limit force generation in the muscle-tendon unit [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. Downregulation of spinal inhibition, presumably guided by Renshaw cell activity [\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e], is regulated by central descending pathways and has been observed in previous studies [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan additionalcitationids=\"CR45\" citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]. This is evidenced by the proportionally greater improvement of MU discharge rate after eccentric-only than concentric-only training [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. Downregulation of spinal inhibition is also evident after maximal concentric training [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]; however, this may be more significant after maximal eccentric training, which plays a more critical role in increasing MVC\u003csub\u003eECC\u003c/sub\u003e due to the more pronounced protective mechanisms during the initial stages of exercise, attributable to higher mechanical demands [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. This could also be due to lower voluntary activation during eccentric contractions, commonly found in resistance training studies involving participants naive to eccentric training [\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e, \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRegarding muscle morphological factors, it is possible that not only contractile muscle structures but also noncontractile structures such as tendon play a role in the greater increases in MVC\u003csub\u003eECC\u003c/sub\u003e following eccentric-only than concentric-only training. It has been documented that mechanical tension, exercise-induced muscle damage, and metabolic stress mediate the hypertrophic signalling response to training [\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e]. Eccentric-only training may provide higher mechanical stress to induce greater protein signalling cascades and acute inflammatory responses to muscle damage, which are thought to upregulate protein synthesis more effectively when compared with concentric-only training [\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e, \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e]. In contrast to concentric contractions, EMG activity does not change with increasing muscle-tendon force in eccentric contractions [\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e], indicating that noncontractile elements significantly contribute to force production [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e]. Noncontractile protein such as titin, connective tissue surrounding muscle fibers and fascicles (i.e., extracellular matrix: ECM) are stretched during the lengthening of the muscle-tendon unit [\u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e57\u003c/span\u003e]. This stretching induces adaptations in the connective tissue structures over time, increasing their ability to resist tensile forces and improve sarcomere integrity during eccentric contraction [\u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e]. The role of titin in force production during eccentric, but less in concentric or isometric contraction has been documented [\u003cspan additionalcitationids=\"CR59 CR60 CR61\" citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e62\u003c/span\u003e]. Titin molecules differ between fiber types, being larger and stiffer in type II than in type I [\u003cspan citationid=\"CR59\" class=\"CitationRef\"\u003e59\u003c/span\u003e]. While they also act as mediators for hypertrophic signalling [\u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e], this may explain beneficial effect of eccentric training on type II fibers [\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e] and muscle hypertrophy [\u003cspan citationid=\"CR63\" class=\"CitationRef\"\u003e63\u003c/span\u003e, \u003cspan citationid=\"CR64\" class=\"CitationRef\"\u003e64\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe time course of muscle-tendon morphological adaptations is longer than that of neural adaptations [\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e, \u003cspan additionalcitationids=\"CR66 CR67\" citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR68\" class=\"CitationRef\"\u003e68\u003c/span\u003e], thus the beneficial effects of eccentric-only training over concentric-only training on the structural components of the muscle-tendon unit, may take longer to be observed. This speculation aligns with the results of our meta-regression, which showed that the superiority of eccentric-only training for MVC\u003csub\u003eECC\u003c/sub\u003e improvement was more pronounced in the studies with longer training durations [\u003cspan additionalcitationids=\"CR70 CR71 CR72\" citationid=\"CR69\" class=\"CitationRef\"\u003e69\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR73\" class=\"CitationRef\"\u003e73\u003c/span\u003e] (please also see Table S4 in ESM). Previous studies have also suggested that a longer recovery time after eccentric than concentric training due to muscle damage may be related to the longer time taken for neuromuscular adaptations to be observed after eccentric training [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR74\" class=\"CitationRef\"\u003e74\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn contract, the present study showed no significant difference between eccentric-only and concentric-only strength training for changes in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). It could be speculated that the neural and morphological adaptations mentioned above are not specific to eccentric-only training. It may be that the adaptations are also induced by concentric-only training, which induced similar increases in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e increases after training (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). Since neural and morphological adaptations for strength gains could be greater after eccentric-only than concentric-only training as discussed above, it seems reasonable to assume that eccentric-only training could also increase MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e greater than concentric-only training, but this was not found. An extra excitatory descending drive to compensate for spinal inhibition (recurrent inhibition and Ib afferent inhibition) may increase through the activation of different cortical areas in eccentric versus concentric contractions [\u003cspan citationid=\"CR75\" class=\"CitationRef\"\u003e75\u003c/span\u003e, \u003cspan citationid=\"CR76\" class=\"CitationRef\"\u003e76\u003c/span\u003e]. Nevertheless, the factors contributing to the modulation of voluntary activation at spinal and supraspinal levels remain unknown [\u003cspan citationid=\"CR77\" class=\"CitationRef\"\u003e77\u003c/span\u003e]. It has been reported that hypertrophic responses to eccentric versus concentric contractions are achieved through different adaptations in muscle architecture [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Eccentric training results in a significantly greater increase in fascicle length, while concentric training promotes greater changes in pennation angle, likely reflecting the differential addition of sarcomeres either in series or in parallel, respectively [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR78\" class=\"CitationRef\"\u003e78\u003c/span\u003e]. Increased muscle cross-sectional area due to eccentric training has been associated with increased fascicle length rather than changes in pennation angle [\u003cspan additionalcitationids=\"CR80\" citationid=\"CR79\" class=\"CitationRef\"\u003e79\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR81\" class=\"CitationRef\"\u003e81\u003c/span\u003e]. Thus, while both training modes result in more contractile material placed in parallel, predisposing to greater MVC muscle force production in all contraction modes, it may be that changes in fascicle length after eccentric-only training are associated with increases in muscle shortening speed and force production during high-speed dynamic contractions. It is interesting to investigate whether eccentric-only training can increase muscle power and rate of force development better than concentric-only training.\u003c/p\u003e \u003cp\u003eIt has been shown that an increase in MVC\u003csub\u003eCON\u003c/sub\u003e is specific to the velocity used in concentric training [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The results of subgroup analyses in the present study indicate that higher-velocity concentric-only training was more effective for improving slower MVC\u003csub\u003eCON\u003c/sub\u003e when compared to higher-velocity isokinetic eccentric-only training (Table S5 in ESM). This finding contrasts with the finding of a previous study showing that eccentric training with contractions lasting for 2\u0026ndash;6 seconds increased concentric 1-RM similarly [\u003cspan citationid=\"CR82\" class=\"CitationRef\"\u003e82\u003c/span\u003e]. Furthermore, previous studies indicated that fast eccentric training increased muscle thickness [\u003cspan citationid=\"CR64\" class=\"CitationRef\"\u003e64\u003c/span\u003e] and IIb fiber composition [\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e]. This could theoretically benefit increases in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e, regardless of the movement velocity. Conversely, by increasing the velocity of eccentric contractions, the muscle-tendon force-generating capacity may rely more on noncontractile structures [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e, \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e, \u003cspan citationid=\"CR78\" class=\"CitationRef\"\u003e78\u003c/span\u003e]. This could lead to more favourable adaptations in noncontractile than contractile elements, which might explain why faster eccentric-only training does not necessary increase MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e greater than concentric-only training. It is interesting to investigate further what determines specificity and non-specificity of resistance training with different contraction modes.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec22\" class=\"Section2\"\u003e \u003ch2\u003e4.2 Strengths and limitations\u003c/h2\u003e \u003cp\u003e This review with meta-analyses was conducted rigorously, with a priori specifications for all criteria. A major strength of our analyses was the high number of included studies and outcomes and comparisons, which enhances the robustness of the results. We also adhered to the recommendations by Kadlec et al. [\u003cspan citationid=\"CR84\" class=\"CitationRef\"\u003e84\u003c/span\u003e] to further improve the result quality. Additionally, performing sensitivity analyses provided us with insights into the influence of outliers and smaller studies on the overall effects.\u003c/p\u003e \u003cp\u003eHowever, the findings of this review should be interpreted with some limitations, which in turn offer useful guidance for future research. Quality of the study results was very-low to low due to high between-study inconsistency, wide confidence intervals and publication bias. Although we attempted to explore the causes of the heterogeneity by performing subgroup analyses and meta-regressions, we could only explain variability with one moderator for each of MVC\u003csub\u003eECC\u003c/sub\u003e and MVC\u003csub\u003eCON\u003c/sub\u003e improvements. Moreover, a small number of studies were eligible for inclusion in some subgroups (for example, only one study included trained participants) (Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e; Tables S4-6 in ESM), and continuous moderator values were homogeneous across the studies (for example, age ranged from 20 to 38), similar to problems identified in previous studies in the field [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. It is also important to note that some of the subgroups analysed included fewer than the suggested eight effect sizes [\u003cspan citationid=\"CR85\" class=\"CitationRef\"\u003e85\u003c/span\u003e] what increases the risk of overfitting. Moreover, moderator variables were not reported in all studies (Tables S4-6 in ESM). Therefore, more studies are required in the future to detail the variability of the results. This is particularly true for MVC\u003csub\u003eISO\u003c/sub\u003e, where no moderator could explain the variability of the effects from our study.\u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, concentric-only training increased MVC\u003csub\u003eISO\u003c/sub\u003e by 17%, followed by MVC\u003csub\u003eCON\u003c/sub\u003e at 14%, and MVC\u003csub\u003eECC\u003c/sub\u003e at 10%. The comparison between training mode specific (i.e., MVC\u003csub\u003eCON\u003c/sub\u003e) and non-specific (i.e., MVC\u003csub\u003eISO\u003c/sub\u003e) gains should be interpreted with caution, as a lower number of studies were eligible to be included in the MVC\u003csub\u003eISO\u003c/sub\u003e analysis than in the MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e. Readers should also be cautious about generalising the findings of this review. Results are the most generalizable to single-joint exercises and maximal eccentric/concentric-only training using an isokinetic dynamometer, which might be less applicable in practice. Nevertheless, previous review showed that specific strength gains could be similar and even more pronounced when training was performed with isotonic than isokinetic modality [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Therefore, future studies are required to quantify the modality-specificity of the strength gains. Our results are most generalizable to healthy, middle-aged, moderately trained individuals naive to eccentric training, while only one study included strength-trained athletes.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec23\" class=\"Section2\"\u003e \u003ch2\u003e4.3 Practical implications and future research\u003c/h2\u003e \u003cp\u003eBoth eccentric and concentric muscle contractions are included in majority of human movements. Therefore, it is crucial to consider the specific mechanisms associated with each type of contraction independently and in combination. For the maintenance or improvement of health and quality of life related to muscle strength and mass [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] eccentric contractions should be emphasized during resistance exercise training due to more versatile strength improvements by eccentric training. Moreover, MVC\u003csub\u003eECC\u003c/sub\u003e predisposes individuals to better stretch-shortening cycle performance [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], particularly evident in changes of direction [\u003cspan citationid=\"CR86\" class=\"CitationRef\"\u003e86\u003c/span\u003e] and jumping performance [\u003cspan citationid=\"CR87\" class=\"CitationRef\"\u003e87\u003c/span\u003e, \u003cspan citationid=\"CR88\" class=\"CitationRef\"\u003e88\u003c/span\u003e]. Eccentric training has proven superior to concentric training for improving the stiffness of elastic elements [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] and the recoil of elastic energy [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Thus, the present study results recommend the use of maximal eccentric training as the preferred method to increase MVC\u003csub\u003eECC\u003c/sub\u003e and consequently enhance performance, while the potential of concentric training for improving MVC\u003csub\u003eECC\u003c/sub\u003e is limited.\u003c/p\u003e \u003cp\u003eThe present study results indicate that the transfer of strength gain from fast maximal eccentric-only training to slow concentric strength is limited; therefore, fast eccentric contractions may not be ideal for improving slow MVC\u003csub\u003eCON\u003c/sub\u003e. Additionally, as the superiority of eccentric-only to concentric-only training for improving MVC\u003csub\u003eECC\u003c/sub\u003e increases over time, strength and conditioning coaches should plan a longer training period to maximize neuromuscular adaptations and performance enhancements [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR74\" class=\"CitationRef\"\u003e74\u003c/span\u003e]. Performance testing in research settings should be conducted at later stages post-training protocol to obtain credible insights into the underlying mechanisms or adaptations. Future research should also involve more trained participants and extend over longer periods to ensure comprehensive results.\u003c/p\u003e \u003cp\u003eFurthermore, given the higher within-set fatigue tolerance and possible muscle damage specific to eccentric contractions, the dose-response relationships of eccentric training protocols for maximizing strength gains and minimizing the overtraining effect [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e, \u003cspan citationid=\"CR74\" class=\"CitationRef\"\u003e74\u003c/span\u003e] should be carefully considered in future research. This aspect was overlooked in the studies included in our review, with none reporting the conduct of familiarization protocols despite the maximal training intensity expected to cause severe muscle damage [\u003cspan citationid=\"CR89\" class=\"CitationRef\"\u003e89\u003c/span\u003e, \u003cspan citationid=\"CR90\" class=\"CitationRef\"\u003e90\u003c/span\u003e] which can result in suppressed force production and suboptimal training intensity [\u003cspan citationid=\"CR91\" class=\"CitationRef\"\u003e91\u003c/span\u003e, \u003cspan citationid=\"CR92\" class=\"CitationRef\"\u003e92\u003c/span\u003e]; potentially limiting strength gains in the early stages of training.\u003c/p\u003e \u003cp\u003eEccentric exercise-mode specificity of MVC\u003csub\u003eECC\u003c/sub\u003e gain [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] was confirmed by the results of the present study. Nevertheless, further randomized controlled studies are necessary to elucidate the mechanisms underlying the variability of the effects and to assess the applicability of the results to diverse populations, including young and elderly individuals, across various training modalities, and in the context of more complex, multi-joint human movements.\u003c/p\u003e \u003c/div\u003e"},{"header":"5 Conclusions","content":"\u003cp\u003eThe present review with meta-analysis demonstrates the superiority of isokinetic eccentric-only training over concentric-only training in improving MVC\u003csub\u003eECC\u003c/sub\u003e. Furthermore, the results indicate a higher transfer effect between training modes with eccentric-only training, while its effects on MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e were similar to those of concentric-only training. It is important to note that the effect of eccentric-only training on MVC\u003csub\u003eCON\u003c/sub\u003e is greater than the effect of concentric-only training on MVC\u003csub\u003eECC\u003c/sub\u003e, and the magnitude of increase in MVC\u003csub\u003eISO\u003c/sub\u003e is greater for eccentric-only than concentric-only training. This suggests that eccentric-only training is more versatile than concentric-only training. It seems that despite the unique neural control and muscle-force generating mechanisms involved, eccentric-only strength training leads to adaptations over time that better predispose the muscles' overall force-generating capacities compared to concentric-only strength training. Therefore, the use of eccentric training should be actively promoted in strength and conditioning practice.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e Not applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material:\u003c/strong\u003e All data generated or analysed during this study are included in the article and its Supplementary files.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no conflicts of interest relevant to the content of this review.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThe Slovenian Research Agency\u0026apos;s program \u0026apos;Kinesiology of Monostructural, Polystructural, and Conventional Sports (P5-0147)\u0026apos; provided partial salary support for DS. Additionally, DS received financial support for a visiting professorship at the Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University in Australia for three months, through the \u0026apos;[RSF] Internal Call for Co-Financing Mobility of Assistants, Assistants with Doctorates, and Higher Education Teachers (Educational Staff) at Higher Education Institutions Abroad for 2023-2024 (B.II.3)\u0026apos; from the University of Ljubljana, Slovenia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u0026nbsp;\u003c/strong\u003eDS performed the analyses, visualized the data, and wrote the first draft of the manuscript. DS and KN contributed equally to the conception and design of the study, interpretation of the data, drafting and critical revision of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eThe authors would like to thank Renan Vieira Barreto for his valuable comments during the preparation of this manuscript. The authors acknowledge the funding bodies to make this collaborative study possible.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSuchomel TJ, Nimphius S, Stone MH. The importance of muscular strength in athletic performance. Sport Med. 2016;46(10):1419\u0026ndash;49. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-016-0486-0\u003c/span\u003e\u003cspan address=\"10.1007/s40279-016-0486-0\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbou Sawan S, Nunes EA, Lim C, McKendry J, Phillips SM. The health benefits of resistance exercise: beyond hypertrophy and big weights. Exerc Sport Mov. 2023;1(1):e00002. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/ESM.0000000000000001\u003c/span\u003e\u003cspan address=\"10.1249/ESM.0000000000000001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSuchomel TJ, Nimphius S, Bellon CR, Stone MH. The importance of muscular strength: training considerations. Sport Med. 2018;48(4):765\u0026ndash;85. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-018-0862-z\u003c/span\u003e\u003cspan address=\"10.1007/s40279-018-0862-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHedayatpour N, Falla D. Physiological and neural adaptations to eccentric exercise: mechanisms and considerations for training. Biomed Res Int. 2015. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1155/2015/193741\u003c/span\u003e\u003cspan address=\"10.1155/2015/193741\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoig M, O\u0026rsquo;Brien K, Kirk G, Murray R, McKinnon P, Shadgan B, Reid WD. The effects of eccentric versus concentric resistance training on muscle strength and mass in healthy adults: A systematic review with meta-analysis. Br J Sports Med. 2009;43(8):556\u0026ndash;68. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/bjsm.2008.051417\u003c/span\u003e\u003cspan address=\"10.1136/bjsm.2008.051417\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGabriel DA, Kamen G, Frost G. Neural Adaptations to Resistive Exercise. Sport Med. 2006;36(2):133\u0026ndash;49. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2165/00007256-200636020-00004\u003c/span\u003e\u003cspan address=\"10.2165/00007256-200636020-00004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMorrissey MC, Harman EA, Johnson MJ. Resistance training modes:Specificity and effectiveness. Med Sci Sport Exerc. 1995;27(5):648\u0026ndash;60. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/00005768-199505000-00006\u003c/span\u003e\u003cspan address=\"10.1249/00005768-199505000-00006\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNuzzo JL, Pinto MD, Nosaka K, Steele J. The eccentric:concentric strength ratio of human skeletal muscle in vivo: Meta-analysis of the influences of sex, age, joint action, and velocity. Sport Med. 2023. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-023-01851-y\u003c/span\u003e\u003cspan address=\"10.1007/s40279-023-01851-y\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDouglas J, Pearson S, Ross A, McGuigan M. Eccentric exercise: physiological characteristics and acute responses. Sport Med. 2017;47(4):663\u0026ndash;75. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-016-0624-8\u003c/span\u003e\u003cspan address=\"10.1007/s40279-016-0624-8\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDouglas J, Pearson S, Ross A, McGuigan M. Chronic adaptations to eccentric training: A systematic review. Sport Med. 2017;47(5):917\u0026ndash;41. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-016-0628-4\u003c/span\u003e\u003cspan address=\"10.1007/s40279-016-0628-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFranchi M, Reeves N, Narici M. Skeletal muscle remodeling in response to eccentric vs. concentric loading: Morphological, molecular, and metabolic adaptations. Front Physiol. 2017;8(447):1\u0026ndash;16. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3389/fphys.2017.00447\u003c/span\u003e\u003cspan address=\"10.3389/fphys.2017.00447\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eToigo M, Boutellier U. New fundamental resistance exercise determinants of molecular and cellular muscle adaptations. Eur J Appl Physiol. 2006;97(6):643\u0026ndash;63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-006-0238-1\u003c/span\u003e\u003cspan address=\"10.1007/s00421-006-0238-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMalliaras P, Kamal B, Nowell A, Farley T, Dhamu H, Simpson V, Morrissey D, Langberg H, Maffulli N, Reeves ND. Patellar tendon adaptation in relation to load-intensity and contraction type. J Biomech. 2013;46(11):1893\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jbiomech.2013.04.022\u003c/span\u003e\u003cspan address=\"10.1016/j.jbiomech.2013.04.022\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaeo S, Shan X, Otsuka S, Kanehisa H, Kawakami Y. Neuromuscular adaptations to work-matched maximal eccentric versus concentric training. Med Sci Sports Exerc. 2018;50(8):1629\u0026ndash;40. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/MSS.0000000000001611\u003c/span\u003e\u003cspan address=\"10.1249/MSS.0000000000001611\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuclay J, Martin A, Robbe A, Pousson M. Spinal reflex plasticity during maximal dynamic contractions after eccentric training. Med Sci Sports Exerc. 2008;40(4):722\u0026ndash;34. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/MSS.0b013e31816184dc\u003c/span\u003e\u003cspan address=\"10.1249/MSS.0b013e31816184dc\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHigbie EJ, Cureton KJ, Warren GL, Prior BM. Effects of concentric and eccentric training on muscle strength, cross-sectional area, and neural activation. J Appl Physiol. 1996;81(5):2173\u0026ndash;81. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.1996.81.5.2173\u003c/span\u003e\u003cspan address=\"10.1152/jappl.1996.81.5.2173\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNuzzo JL, Pinto MD, Nosaka K. Connective adaptive resistance exercise (CARE) machines for accentuated eccentric and eccentric\u0026ndash;only exercise: introduction to an emerging concept. Sport Med. 2023. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-023-01842-z\u003c/span\u003e\u003cspan address=\"10.1007/s40279-023-01842-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFranchi MV, Maffiuletti NA. Distinct modalities of eccentric exercise: Different recipes, not the same dish. J Appl Physiol. 2019;127(3):881\u0026ndash;3. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00093.2019\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00093.2019\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilk M, Zajac A, Tufano JJ. The influence of movement tempo during resistance training on muscular strength and hypertrophy responses: A review. Sport Med. 2021;51(8):1629\u0026ndash;50. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-021-01465-2\u003c/span\u003e\u003cspan address=\"10.1007/s40279-021-01465-2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStone MH, Hornsby WG, Suarez DG, Duca M, Pierce KC. Training Specificity for Athletes: Emphasis on Strength-Power Training: A Narrative Review. J Funct Morphol Kinesiol. 2022;7(4). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3390/jfmk7040102\u003c/span\u003e\u003cspan address=\"10.3390/jfmk7040102\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGault ML, Willems MET. Aging, functional capacity and eccentric exercise training. Aging Dis. 2013;4(6):351\u0026ndash;63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.14336/AD.2013.0400351\u003c/span\u003e\u003cspan address=\"10.14336/AD.2013.0400351\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMangine GT, Gonzalez AM, Townsend JR, Wells AJ, Beyer KS, Miramonti AA, Ratamess NA, Stout JR, Hoffman JR. Influence of baseline muscle strength and size measures on training adaptations in resistance-trained men. Int J Exerc Sci. 2018;11(4):198\u0026ndash;213.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYoshida R, Kasahara K, Murakami Y, Sato S, Nosaka K, Nakamura M. Less fatiguability in eccentric than concentric repetitive maximal muscle contractions. Eur J Appl Physiol. 2023;123(7):1553\u0026ndash;65. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-023-05178-4\u003c/span\u003e\u003cspan address=\"10.1007/s00421-023-05178-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchoenfeld BJ, Ogborn DI, Vigotsky AD, Franchi MV, Krieger JW. Hypertrophic effects of concentric vs. eccentric muscle actions. J Strength Cond Res. 2017;31(9):2599\u0026ndash;608. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/JSC.0000000000001983\u003c/span\u003e\u003cspan address=\"10.1519/JSC.0000000000001983\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVogt M, Hoppeler HH. Eccentric exercise: Mechanisms and effects when used as training regime or training adjunct. J Appl Physiol. 2014;116(11):1446\u0026ndash;54. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00146.2013\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00146.2013\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePage MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE, Chou R, Glanville J, Grimshaw JM, Hr\u0026oacute;bjartsson A, Lalu MM, Li T, Loder EW, Mayo-Wilson E, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. J Clin Epidemiol. 2022. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jclinepi.2021.03.001\u003c/span\u003e\u003cspan address=\"10.1016/j.jclinepi.2021.03.001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCole V, Boutet M. ResearchRabbit (product review). J Can Heal Libr Assoc. 2023;44(2):43\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.29173/jchla29699\u003c/span\u003e\u003cspan address=\"10.29173/jchla29699\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGreenhalgh T, Peacock R. Effectiveness and efficiency of search methods in systematic reviews of complex evidence: Audit of primary sources. Br Med J. 2005;331(7524):1064\u0026ndash;5. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/bmj.38636.593461.68\u003c/span\u003e\u003cspan address=\"10.1136/bmj.38636.593461.68\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeir JP, Housh TJ, Weir LL. Electromyographic evaluation of joint angle specificity and cross-training after isometric training. J Appl Physiol. 1994;77(1):197\u0026ndash;201. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.1994.77.1.197\u003c/span\u003e\u003cspan address=\"10.1152/jappl.1994.77.1.197\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLanza MB, Balshaw TG, Folland JP. Is the joint-angle specificity of isometric resistance training real? And if so, does it have a neural basis? Eur J Appl Physiol. 2019;119(11\u0026ndash;12):2465\u0026ndash;76. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-019-04229-z\u003c/span\u003e\u003cspan address=\"10.1007/s00421-019-04229-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBorenstein M, Hedges L, Higgins J, Rothstein H. Introduction to Meta-Analysis. Chichester, UK: Wiley; 2009. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/epdf/10.1002/9780470743386\u003c/span\u003e\u003cspan address=\"epdf/10.1002/9780470743386\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHortobagyi T, Devita P, Money J, Barrier J. Effects of standard and eccentric overload strength training in young women. Med Sci Sports Exerc. 2001;33(7):1206\u0026ndash;12. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1097/00005768-200107000-00020\u003c/span\u003e\u003cspan address=\"10.1097/00005768-200107000-00020\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePaci M, Bianchini C, Baccini M. Reliability of the PEDro scale: comparison between trials published in predatory and non-predatory journals. Arch Physiother. 2022;12(1):1\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s40945-022-00133-6\u003c/span\u003e\u003cspan address=\"10.1186/s40945-022-00133-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHoffmann TC, Glasziou PP, Boutron I, Milne R, Perera R, Moher D, Altman DG, Barbour V, Macdonald H, Johnston M, Kadoorie SEL, Dixon-Woods M, McCulloch P, Wyatt JC, Phelan AWC, Michie S. Better reporting of interventions: Template for intervention description and replication (TIDieR) checklist and guide. BMJ. 2014. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/bmj.g1687\u003c/span\u003e\u003cspan address=\"10.1136/bmj.g1687\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuyatt G, Oxman AD, Akl EA, Kunz R, Vist G, Brozek J, Norris S, Falck-Ytter Y, Glasziou P, Debeer H, Jaeschke R, Rind D, Meerpohl J, Dahm P, Sch\u0026uuml;nemann HJ. GRADE guidelines: 1. Introduction - GRADE evidence profiles and summary of findings tables. J Clin Epidemiol. 2011;64(4):383\u0026ndash;94. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jclinepi.2010.04.026\u003c/span\u003e\u003cspan address=\"10.1016/j.jclinepi.2010.04.026\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, Sch\u0026uuml;nemann HJ. GRADE: An emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008;336(7650):924\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/bmj.39489.470347.AD\u003c/span\u003e\u003cspan address=\"10.1136/bmj.39489.470347.AD\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuyatt GH, Oxman AD, Kunz R, Brozek J, Alonso-Coello P, Rind D, Devereaux PJ, Montori VM, Freyschuss B, Vist G, Jaeschke R, Williams JW, Murad MH, Sinclair D, Falck-Ytter Y, Meerpohl J, Whittington C, Thorlund K, et al. GRADE guidelines 6. Rating the quality of evidence - Imprecision. J Clin Epidemiol. 2011;64(12):1283\u0026ndash;93. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jclinepi.2011.01.012\u003c/span\u003e\u003cspan address=\"10.1016/j.jclinepi.2011.01.012\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePustejovsky JE, Tipton E. Meta-analysis with robust variance estimation: expanding the range of working models. Prev Sci. 2022;23(3):425\u0026ndash;38. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s11121-021-01246-3\u003c/span\u003e\u003cspan address=\"10.1007/s11121-021-01246-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoeyaert M, Ugille M, Beretvas N, Ferron J, Bunuan R, Van den Noortgate W. Methods for dealing with multiple outcomes in meta-analysis: a comparison between averaging effect sizes, robust variance estimation and multilevel meta-analysis. Int J Soc Res Methodol. 2017;20(6):559\u0026ndash;72. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1080/13645579.2016.1252189\u003c/span\u003e\u003cspan address=\"10.1080/13645579.2016.1252189\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHopkins W, Marshall S, Batterham A, Hanin J. Progressive statistics for studies in sports medicine and exercise science. Med Sci Sport Exerc. 2009;41(1):3\u0026ndash;13. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/MSS.0b013e31818cb278\u003c/span\u003e\u003cspan address=\"10.1249/MSS.0b013e31818cb278\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHiggins JPT, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. Br Med J. 2003;327(7414):557\u0026ndash;60. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/bmj.327.7414.557\u003c/span\u003e\u003cspan address=\"10.1136/bmj.327.7414.557\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOuzzani M, Hammady H, Fedorowicz Z, Elmagarmid A. Rayyan-a web and mobile app for systematic reviews. Syst Rev. 2016;5(1):1\u0026ndash;11. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s13643-016-0384-4\u003c/span\u003e\u003cspan address=\"10.1186/s13643-016-0384-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHortob\u0026aacute;gyi T, Hill JP, Houmard JA, Fraser DD, Lambert NJ, Israel RG. Adaptive responses to muscle lengthening and shortening in humans. J Appl Physiol. 1996;80(3):765\u0026ndash;72. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.1996.80.3.765\u003c/span\u003e\u003cspan address=\"10.1152/jappl.1996.80.3.765\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHortob\u0026aacute;gyi T, Barrier J, Beard D, Braspennincx J, Koens P, Devita P, Dempsey L, Lambert J. Greater initial adaptations to submaximal muscle lengthening than maximal shortening. J Appl Physiol. 1996;81(4):1677\u0026ndash;82. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.1996.81.4.1677\u003c/span\u003e\u003cspan address=\"10.1152/jappl.1996.81.4.1677\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAagaard P. Training-induced changes in neural function. Exerc Sport Sci Rev. 2003;31(2):61\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1097/00003677-200304000-00002\u003c/span\u003e\u003cspan address=\"10.1097/00003677-200304000-00002\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarru\u0026eacute;-Belou S, Marque P, Duclay J. Recurrent inhibition is higher in eccentric compared to isometric and concentric maximal voluntary contractions. Acta Physiol. 2018;223(4). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/apha.13064\u003c/span\u003e\u003cspan address=\"10.1111/apha.13064\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSale DG. Neural adaptation to resistance training. Med Sci Sports Exerc. 1988;20(5):135\u0026ndash;45. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/00005768-198810001-00009\u003c/span\u003e\u003cspan address=\"10.1249/00005768-198810001-00009\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAagaard P, Simonsen EB, Andersen JL, Magnusson P, Dyhre-Poulsen P. Neural adaptation to resistance training: Changes in evoked V-wave and H-reflex responses. J Appl Physiol. 2002;92(6):2309\u0026ndash;18. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.01185.2001\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.01185.2001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAagaard P, Simonsen EB, Andersen JL, Magnusson SP, Halkj\u0026aelig;r-Kristensen J, Dyhre-Poulsen P. Neural inhibition during maximal eccentric and concentric quadriceps contraction: Effects of resistance training. J Appl Physiol. 2000;89(6):2249\u0026ndash;57. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.2000.89.6.2249\u003c/span\u003e\u003cspan address=\"10.1152/jappl.2000.89.6.2249\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAagaard P. Spinal and supraspinal control of motor function during maximal eccentric muscle contraction: Effects of resistance training. J Sport Heal Sci. 2018;7(3):282\u0026ndash;93. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jshs.2018.06.003\u003c/span\u003e\u003cspan address=\"10.1016/j.jshs.2018.06.003\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBeltman JGM, Sargeant AJ, Van Mechelen W, De Haan A. Voluntary activation level and muscle fiber recruitment of human quadriceps during lengthening contractions. J Appl Physiol. 2004;97(2):619\u0026ndash;26. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.01202.2003\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.01202.2003\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBabault N, Pousson M, Ballay Y, Van Hoecke J. Activation of human quadriceps femoris during isometric, concentric, and eccentric contractions. J Appl Physiol. 2001;91(6):2628\u0026ndash;34. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/jappl.2001.91.6.2628\u003c/span\u003e\u003cspan address=\"10.1152/jappl.2001.91.6.2628\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchoenfeld BJ. The mechanisms of muscle hypertrophy and their application to resistance training. J Strength Cond Res. 2010;24(10):2857\u0026ndash;72. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/JSC.0b013e3181e840f3\u003c/span\u003e\u003cspan address=\"10.1519/JSC.0b013e3181e840f3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCoffey VG, Hawley JA. The molecular bases of training adaptation. Sport Med. 2007;37(9):737\u0026ndash;63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2165/00007256-200737090-00001\u003c/span\u003e\u003cspan address=\"10.2165/00007256-200737090-00001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKomi PV, Kaneko M, Aura O. EMG activity of the leg extensor muscles with special reference to mechanical efficiency in concentric and eccentric exercise. Int J Sports Med. 1987;8:22\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1055/s-2008-1025700\u003c/span\u003e\u003cspan address=\"10.1055/s-2008-1025700\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePaddon-Jones D, Leveritt M, Lonergan A, Abernethy P. Adaptation to chronic eccentric exercise in humans: The influence of contraction velocity. Eur J Appl Physiol. 2001;85(5):466\u0026ndash;71. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s004210100467\u003c/span\u003e\u003cspan address=\"10.1007/s004210100467\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHyldahl RD, Chen TC, Nosaka K. Mechanisms and mediators of the skeletal muscle repeated bout effect. Exerc Sport Sci Rev. 2017;45(1):24\u0026ndash;33. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/JES.0000000000000095\u003c/span\u003e\u003cspan address=\"10.1249/JES.0000000000000095\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKr\u0026uuml;ger M, K\u0026ouml;tter S. Titin, a central mediator for hypertrophic signaling, exercise-induced mechanosignaling and skeletal muscle remodeling. Front Physiol. 2016;7:1\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3389/fphys.2016.00076\u003c/span\u003e\u003cspan address=\"10.3389/fphys.2016.00076\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePrado LG, Makarenko I, Andresen C, Kr\u0026uuml;ger M, Opitz CA, Linke WA. Isoform diversity of giant proteins in relation to passive and active contractile properties of rabbit skeletal muscles. J Gen Physiol. 2005;126(5):461\u0026ndash;80. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1085/jgp.200509364\u003c/span\u003e\u003cspan address=\"10.1085/jgp.200509364\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNishikawa KC, Lindstedt SL, LaStayo PC. Basic science and clinical use of eccentric contractions: History and uncertainties. J Sport Heal Sci. 2018;7(3):265\u0026ndash;74. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jshs.2018.06.002\u003c/span\u003e\u003cspan address=\"10.1016/j.jshs.2018.06.002\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTomalka A. Eccentric muscle contractions: from single muscle fibre to whole muscle mechanics. Pflugers Arch Eur J Physiol. 2023;475(4):421\u0026ndash;35. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00424-023-02794-z\u003c/span\u003e\u003cspan address=\"10.1007/s00424-023-02794-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHerzog W. Why are muscles strong, and why do they require little energy in eccentric action? J Sport Heal Sci. 2018;7(3):255\u0026ndash;64. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jshs.2018.05.005\u003c/span\u003e\u003cspan address=\"10.1016/j.jshs.2018.05.005\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAzevedo PHSM, Oliveira MGD, Schoenfeld BJ. Effect of different eccentric tempos on hypertrophy and strength of the lower limbs. Biol Sport. 2022;39(2):443\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.5114/BIOLSPORT.2022.105335\u003c/span\u003e\u003cspan address=\"10.5114/BIOLSPORT.2022.105335\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarthing JP, Chilibeck PD. The effects of eccentric and concentric training at different velocities on muscle hypertrophy. Eur J Appl Physiol. 2003;89(6):578\u0026ndash;86. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-003-0842-2\u003c/span\u003e\u003cspan address=\"10.1007/s00421-003-0842-2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFolland JP, Williams AG. The adaptations to strength training: Morphological and neurological contributions to increased strength. Sport Med. 2007;37(2):145\u0026ndash;68. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2165/00007256-200737020-00004\u003c/span\u003e\u003cspan address=\"10.2165/00007256-200737020-00004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKubo K, Ikebukuro T, Yata H, Tsunoda N, Kanehisa H. Time course of changes in muscle and tendon properties during strength training and detraining. Strength Cond Res. 2010;24(2):322\u0026ndash;31. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/JSC.0b013e3181c865e2\u003c/span\u003e\u003cspan address=\"10.1519/JSC.0b013e3181c865e2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHughes DC, Ellefsen S, Baar K. Adaptations to endurance and strength training. Cold Spring Harb Perspect Med. 2018;8(6):1\u0026ndash;17. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1101/cshperspect.a029769\u003c/span\u003e\u003cspan address=\"10.1101/cshperspect.a029769\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSeynnes OR, de Boer M, Narici MV. Early skeletal muscle hypertrophy and architectural changes in response to high-intensity resistance training. J Appl Physiol. 2007;102(1):368\u0026ndash;73. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00789.2006\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00789.2006\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHortobagyi T, Dempsey L, Fraser D, Zheng D, Hamilton G, Lambert J, Dohm L. Changes in muscle strength, muscle fibre size and myofibrillar gene expression after immobilization and retraining in humans. J Physiol. 2000;524(1):293\u0026ndash;304. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/j.1469-7793.2000.00293.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1469-7793.2000.00293.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSeger JY, Thorstensson A. Effects of eccentric versus concentric training on thigh muscle strength and EMG. Int J Sports Med. 2005;26(1):45\u0026ndash;52. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1055/s-2004-817892\u003c/span\u003e\u003cspan address=\"10.1055/s-2004-817892\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSeger JY, Arvidsson B, Thorstensson A. Specific effects of eccentric and concentric training on muscle strength and morphology in humans. Eur J Appl Physiol Occup Physiol. 1998;79(1):49\u0026ndash;57. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s004210050472\u003c/span\u003e\u003cspan address=\"10.1007/s004210050472\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMiller LE, Wootten DF, Nickols-Richardson SM, Ramp WK, Steele CR, Cotton JR, Carneal JP, Herbert WG. Isokinetic training increases ulnar bending stiffness and bone mineral in young women. Bone. 2007;41(4):685\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.bone.2007.07.004\u003c/span\u003e\u003cspan address=\"10.1016/j.bone.2007.07.004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNickols-Richardson SM, Miller LE, Wootten DF, Ramp WK, Herbert WG. Concentric and eccentric isokinetic resistance training similarly increases muscular strength, fat-free soft tissue mass, and specific bone mineral measurements in young women. Osteoporos Int. 2007;18(6):789\u0026ndash;96. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00198-006-0305-9\u003c/span\u003e\u003cspan address=\"10.1007/s00198-006-0305-9\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeong CH, McDermott WJ, Elmer SJ, Martin JC. Chronic eccentric cycling improves quadriceps muscle structure and maximum cycling power. Int J Sports Med. 2014;35(7):559\u0026ndash;65. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1055/s-0033-1358471\u003c/span\u003e\u003cspan address=\"10.1055/s-0033-1358471\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKwon YH, Park JW. Different cortical activation patterns during voluntary eccentric and concentric muscle contractions: An fMRI study. NeuroRehabilitation. 2011;29(3):253\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3233/NRE-2011-0701\u003c/span\u003e\u003cspan address=\"10.3233/NRE-2011-0701\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFang Y, Siemionow V, Sahgal V, Xiong F, Yue GH. Distinct brain activation patterns for human maximal voluntary eccentric and concentric muscle actions. Brain Res. 2004;1023(2):200\u0026ndash;12. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.brainres.2004.07.035\u003c/span\u003e\u003cspan address=\"10.1016/j.brainres.2004.07.035\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuchateau J, Baudry S. Insights into the neural control of eccentric contractions. J Appl Physiol. 2013;116(11):1418\u0026ndash;25. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00002.2013\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00002.2013\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNunes JP, Blazevich AJ, Schoenfeld BJ, Kassiano W, Costa BDV, Ribeiro AS, Nakamura M, Nosaka K, Cyrino ES. Determining changes in muscle size and architecture following exercise training: One site does not fit all. J Strength Cond Res. 2024;38(4):787\u0026ndash;90. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/JSC.0000000000004722\u003c/span\u003e\u003cspan address=\"10.1519/JSC.0000000000004722\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaroni BM, Geremia JM, Rodrigues R, De Azevedo Franke R, Karamanidis K, Vaz MA. Muscle architecture adaptations to knee extensor eccentric training: Rectus femoris vs. vastus lateralis. Muscle Nerve. 2013;48(4):498\u0026ndash;506. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/mus.23785\u003c/span\u003e\u003cspan address=\"10.1002/mus.23785\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReeves ND, Maganaris CN, Longo S, Narici MV. Differential adaptations to eccentric versus conventional resistance training in older humans. Exp Physiol. 2009;94(7):825\u0026ndash;33. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1113/expphysiol.2009.046599\u003c/span\u003e\u003cspan address=\"10.1113/expphysiol.2009.046599\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBenford J, Hughes J, Waldron M, Theis N. Concentric versus eccentric training: Effect on muscle strength, regional morphology, and architecture. Transl Sport Med. 2021;4(1):46\u0026ndash;55. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/tsm2.197\u003c/span\u003e\u003cspan address=\"10.1002/tsm2.197\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHandford MJ, Bright TE, Mundy P, Lake J, Theis N, Hughes JD. The need for eccentric speed: A narrative review of the effects of accelerated eccentric actions during resistance-based training. Sport Med. 2022;52(9):2061\u0026ndash;83. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-022-01686-z\u003c/span\u003e\u003cspan address=\"10.1007/s40279-022-01686-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeidner S, Tomalka A, Rode C, Siebert T. How velocity impacts eccentric force generation of fully activated skinned skeletal muscle fibers in long stretches. J Appl Physiol. 2022;133(1):223\u0026ndash;33. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00735.2021\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00735.2021\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKadlec D, Sainani KL, Nimphius S. With great power comes great responsibility: Common errors in meta-analyses and meta-regressions in strength \u0026amp; conditioning research. Sport Med. 2023;53(2):313\u0026ndash;25. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-022-01766-0\u003c/span\u003e\u003cspan address=\"10.1007/s40279-022-01766-0\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJukic I, Castilla AP, Ramos AG, Van Hooren B, McGuigan MR, Helms ER. The Acute and Chronic Effects of Implementing Velocity Loss Thresholds During Resistance Training: A Systematic Review, Meta-Analysis, and Critical Evaluation of the Literature. Sport Med. 2023;53(1):177\u0026ndash;214. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-022-01754-4\u003c/span\u003e\u003cspan address=\"10.1007/s40279-022-01754-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChaabene H, Prieske O, Negra Y, Granacher U. Change of Direction Speed: Toward a Strength Training Approach with Accentuated Eccentric Muscle Actions. Sport Med. 2018;48(8):1773\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s40279-018-0907-3\u003c/span\u003e\u003cspan address=\"10.1007/s40279-018-0907-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNishiumi D, Nishioka T, Saito H, Kurokawa T, Hirose N. Associations of eccentric force variables during jumping and eccentric lower-limb strength with vertical jump performance: A systematic review. PLoS ONE. 2023;18(8):1\u0026ndash;15. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1371/journal.pone.0289631\u003c/span\u003e\u003cspan address=\"10.1371/journal.pone.0289631\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBridgeman LA, McGuigan MR, Gill ND, Dulson DK. Relationships between concentric and eccentric strength and countermovement jump performance in resistance trained men. J Strength Cond Res. 2018;32(1):255\u0026ndash;60. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/JSC.0000000000001539\u003c/span\u003e\u003cspan address=\"10.1519/JSC.0000000000001539\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNosaka K, Newton M. Difference in the magnitude of muscle damage between maximal and submaximal eccentric loading. J Strength Cond Res. 2002;16(2):202\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/1533-4287\u003c/span\u003e\u003cspan address=\"10.1519/1533-4287\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFriden J, Sjostrom M, Ekblom B. Myofibrillar damage following intense eccentric exercise in man. Int J Sports Med. 1983;4(3):170\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1055/s-2008-1026030\u003c/span\u003e\u003cspan address=\"10.1055/s-2008-1026030\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEnglish KL, Loehr JA, Lee SMC, Smith SM. Early-phase musculoskeletal adaptations to different levels of eccentric resistance after 8 weeks of lower body training. Eur J Appl Physiol. 2014;114(11):2264\u0026ndash;80. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-014-2951-5\u003c/span\u003e\u003cspan address=\"10.1007/s00421-014-2951-5\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCheung K, Hume PA, Maxwell L. Delayed onset muscle soreness. Sport Med. 2003;33(2):145\u0026ndash;64. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2165/00007256-200333020-00005\u003c/span\u003e\u003cspan address=\"10.2165/00007256-200333020-00005\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkınoğlu B, Pak\u0026ouml;z B, Yilmaz AE, Shehu SU, Kocahan T. Effect of contraction type at varying angular velocities on isokinetic muscle strength training. J Exerc Rehabil. 2023;19(4):228\u0026ndash;36. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.12965/jer.2346236.118\u003c/span\u003e\u003cspan address=\"10.12965/jer.2346236.118\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarak Y, Ayalon M, Dvir Z. Transferability of strength gains from limited to full range of motion. Med Sci Sports Exerc. 2004;36(8):1413\u0026ndash;20. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/01.MSS.0000135777.01093.21\u003c/span\u003e\u003cspan address=\"10.1249/01.MSS.0000135777.01093.21\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBlazevich AJ, Cannavan D, Coleman DR, Horne S. Influence of concentric and eccentric resistance training on architectural adaptation in human quadriceps muscles. J Appl Physiol. 2007;103(5):1565\u0026ndash;75. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1152/japplphysiol.00578.2007\u003c/span\u003e\u003cspan address=\"10.1152/japplphysiol.00578.2007\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCadore EL, Gonz\u0026aacute;lez-Izal M, Pallar\u0026eacute;s JG, Rodriguez-Falces J, H\u0026auml;kkinen K, Kraemer WJ, Pinto RS, Izquierdo M. Muscle conduction velocity, strength, neural activity, and morphological changes after eccentric and concentric training. Scand J Med Sci Sport. 2014;24(5):343\u0026ndash;52. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/sms.12186\u003c/span\u003e\u003cspan address=\"10.1111/sms.12186\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuncan PW, Chandler JM, Cavanaugh DK, Johnson KR, Buehler AG. Mode and speed specificity of eccentric and concentric exercise training. J Orthop Sports Phys Ther. 1989;11(2):70\u0026ndash;5. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2519/jospt.1989.11.2.70\u003c/span\u003e\u003cspan address=\"10.2519/jospt.1989.11.2.70\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEllenbecker TS, Davies GJ, Rowinski MJ. Concentric versus eccentric isokinetic strengthening of the rotator cuff. Am J Sports Med. 1988;16(1):64\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1177/036354658801600112\u003c/span\u003e\u003cspan address=\"10.1177/036354658801600112\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarthing JP, Chilibeck PD. The effect of eccentric training at different velocities on cross-education. Eur J Appl Physiol. 2003;89(6):570\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-003-0841-3\u003c/span\u003e\u003cspan address=\"10.1007/s00421-003-0841-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHilliard-Robertson PC, Schneider SM, Bishop SL, Guilliams ME. Strength gains following different combined concentric and eccentric exercise regimens. Aviat Sp Environ Med. 2003;74(4):342\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.52082/jssm.2022.200\u003c/span\u003e\u003cspan address=\"10.52082/jssm.2022.200\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKim SY, Ko JB, Farthing JP, Butcher SJ. Investigation of supraspinatus muscle architecture following concentric and eccentric training. J Sci Med Sport. 2015;18(4):378\u0026ndash;82. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jsams.2014.05.007\u003c/span\u003e\u003cspan address=\"10.1016/j.jsams.2014.05.007\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePaschalis V, Nikolaidis MG, Theodorou AA, Panayiotou G, Fatouros IG, Koutedakis Y, Jamurtas AZ. A weekly bout of eccentric exercise is sufficient to induce health-promoting effects. Med Sci Sports Exerc. 2011;43(1):64\u0026ndash;73. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/MSS.0b013e3181e91d90\u003c/span\u003e\u003cspan address=\"10.1249/MSS.0b013e3181e91d90\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRuas CV, Brown LE, Lima CD, Costa PB, Pinto RS. Effect of three different muscle action training protocols on knee strength ratios and performance. J Strength Cond Res. 2018;32(8):2154\u0026ndash;65. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1519/jsc.0000000000002134\u003c/span\u003e\u003cspan address=\"10.1519/jsc.0000000000002134\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRuas CV, Pinto RS, Haff GG, Lima CD, Brown LE. Effects of Different Combinations of Concentric and Eccentric Resistance Training Programs on Traditional and Alternative Hamstrings-to-Quadriceps Ratios. Sports. 2019;221:1\u0026ndash;15. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/doi:10.3390/sports7100221\u003c/span\u003e\u003cspan address=\"doi:10.3390/sports7100221\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMiller LE, Pierson LM, Nickols-Richardson SM, Wootten DF, Selmon SE, Ramp WK, Herbert WG. Knee extensor and flexor torque development with concentric and eccentric isokinetic training. Res Q Exerc Sport. 2012;77(1):58\u0026ndash;63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1080/02701367.2006.10599332\u003c/span\u003e\u003cspan address=\"10.1080/02701367.2006.10599332\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoore DR, Young M, Phillips SM. Similar increases in muscle size and strength in young men after training with maximal shortening or lengthening contractions when matched for total work. Eur J Appl Physiol. 2012;112(4):1587\u0026ndash;92. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-011-2078-x\u003c/span\u003e\u003cspan address=\"10.1007/s00421-011-2078-x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSato S, Yoshida R, Murakoshi F, Sasaki Y, Yahata K, Kasahara K, Nunes JP, Nosaka K, Nakamura M. Comparison between concentric-only, eccentric-only, and concentric\u0026ndash;eccentric resistance training of the elbow flexors for their effects on muscle strength and hypertrophy. Eur J Appl Physiol. 2022;122(12):2607\u0026ndash;14. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00421-022-05035-w\u003c/span\u003e\u003cspan address=\"10.1007/s00421-022-05035-w\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharma KN, Quddus N, Hameed UA, Khan SA, Kumari A, Alghadir AH, Khan M. Mode-specific effects of concentric and eccentric isokinetic training of the hamstring muscle at slow angular velocity on the functional hamstrings-to-quadriceps ratio - a randomized trial. PeerJ. 2022;10. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.7717/peerj.13842\u003c/span\u003e\u003cspan address=\"10.7717/peerj.13842\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKiyomi Takayanagi O, Yoshimura, Hidetoshu Ihara AN. Velocity and mode specificity of concentric and eccentric strength training in knee flexors and extensors. J Phys Ther Sci. 1995;7:57\u0026ndash;63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/doi.org/10.1589/jpts.7.57\u003c/span\u003e\u003cspan address=\"10.1589/jpts.7.57\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTimmins RG, Ruddy JD, Presland J, Maniar N, Shield AJ, Williams MD, Opar DA. Architectural changes of the biceps femoris long head after concentric or eccentric training. Med Sci Sports Exerc. 2016;48(3):499\u0026ndash;508. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1249/MSS.0000000000000795\u003c/span\u003e\u003cspan address=\"10.1249/MSS.0000000000000795\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTomberlin JP, Basford JR, Schwen EE, Orte PA, Scott SG, Laughman RK, Ilstrup DM. Comparative study of isokinetic eccentric and concentric quadriceps training. J Orthop Sports Phys Ther. 1991;14(1):31\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2519/jospt.1991.14.1.31\u003c/span\u003e\u003cspan address=\"10.2519/jospt.1991.14.1.31\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e Summary of the studies with quality evaluation and reporting completeness.\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"912\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\"\u003e\n \u003cp\u003e\u003cstrong\u003eStudy\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasures\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\"\u003e\n \u003cp\u003e\u003cstrong\u003eSample characteristics\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\"\u003e\n \u003cp\u003e\u003cstrong\u003eMuscle groups\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\"\u003e\n \u003cp\u003e\u003cstrong\u003eTraining protocol\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(repetitions, sets, frequency, duration, velocity)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\"\u003e\n \u003cp\u003e\u003cstrong\u003eRisk of\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003ebias\u003c/strong\u003e\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\"\u003e\n \u003cp\u003e\u003cstrong\u003eTIDieR\u003c/strong\u003e\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eAkinoglu 2023\u0026nbsp;[93]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30, 60, 90 120, 150 and 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 32\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eUntrained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 14\u003cbr\u003e\u0026nbsp;CON training n = 14\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors,\u003cbr\u003e\u0026nbsp;knee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e13, 6, 3, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ec\u003c/sup\u003e (30, 180\u0026deg;/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eBarak 2004\u0026nbsp;[94]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u0026nbsp;\u003c/sub\u003eat 30, 90\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at\u003csub\u003e\u0026nbsp;\u003c/sub\u003e45\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 24\u003c/p\u003e\n \u003cp\u003eModerately trained\u003cbr\u003e\u0026nbsp;Sex = F\u003cbr\u003e\u0026nbsp;Velocity 30\u0026deg;/s:\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 14\u003cbr\u003e\u0026nbsp;CON training n = 13\u003c/p\u003e\n \u003cp\u003eVelocity 90\u0026deg;/s:\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 13\u003c/p\u003e\n \u003cp\u003eCON training n = 14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 4, 3, 6,\u0026nbsp;\u003cbr\u003e\u0026nbsp;Velocity 30 or 90\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eBenford 2021\u0026nbsp;[81]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 30 and 90\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 23\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 8\u003cbr\u003e\u0026nbsp;CON training n = 8\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e8, 4, 2, 5,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 30\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eBlazevich 2007\u0026nbsp;[95]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 24\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 12\u003cbr\u003e\u0026nbsp;CON training n = 12\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 5, 3, 10,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 30\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eCadore 2014\u0026nbsp;[96]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 60\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 23\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 11\u003cbr\u003e\u0026nbsp;CON training n = 11\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3.5, 2, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eDuncan 1989\u0026nbsp;[97]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60, 120, 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 24\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eStatus NR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 16\u003cbr\u003e\u0026nbsp;CON training n = 14\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 1, 3, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 120\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003emoderate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eEllenbecker 1988\u0026nbsp;[98]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60, 180, 210\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = NR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eTrained\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 11\u003cbr\u003e\u0026nbsp;CON training n = 11\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eShoulder internal rotators,\u003cbr\u003e\u0026nbsp;shoulder external rotators\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 6, 2, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity MT\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003emoderate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eFarthing 2003\u0026nbsp;[99]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e collapsed between 30 and 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 20\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eUntrained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 13\u003cbr\u003e\u0026nbsp;CON training n = 13\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eElbow flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e8, 6, 3, 8,\u0026nbsp;\u003cbr\u003e\u0026nbsp;Velocity 30\u0026deg;/s or 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e8*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eHigbie 1996\u0026nbsp;[16]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 20\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = F\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 19\u003cbr\u003e\u0026nbsp;CON training n = 16\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3, 3, 10,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eHilliard-Robertson 2003\u0026nbsp;[100]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 33\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 11\u003cbr\u003e\u0026nbsp;CON training n = 11\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 4, 3, 5,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eHortob\u0026aacute;gyi 1996\u0026nbsp;[43]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 45\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 22\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eUntrained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 7\u003cbr\u003e\u0026nbsp;CON training n = 8\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 5, 3, 12,\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eHortob\u0026aacute;gyi 2000\u0026nbsp;[69]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 45\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 22\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 12\u003cbr\u003e\u0026nbsp;CON training n = 12\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 6, 3, 12,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003emoderate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eKim 2015\u0026nbsp;[101]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u0026nbsp;\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 60\u0026deg; shoulder abduction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 28\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eStatus NR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 7\u003cbr\u003e\u0026nbsp;CON training n = 6\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eShoulder abductors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e7, 5, 3, 8,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003ePaschalis 2011\u0026nbsp;[102]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 90\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 21\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = F\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 10\u003cbr\u003e\u0026nbsp;CON training n = 10\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e15, 5, 1, 8,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eRuas 2018\u0026nbsp;[103]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 60\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 23\u003cbr\u003e\u0026nbsp;(2 ECC groups and 1 CON group for knee flexors; 2 CON groups and 1 ECC group for knee extensors)\u003cbr\u003e\u0026nbsp;Untrained\u0026nbsp;\u003cbr\u003e\u0026nbsp;Sex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training all n = 10\u003c/p\u003e\n \u003cp\u003eCON training all n = 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors,\u003cbr\u003e\u0026nbsp;knee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3, 2, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ed\u003c/sup\u003e (60, 90, 120, 150, 180, 210 \u0026deg;/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eRuas 2019\u0026nbsp;[104]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 23\u003cbr\u003e\u0026nbsp;(2 ECC groups and 1 CON group for knee flexors; 2 CON groups and 1 ECC group for knee extensors)\u003cbr\u003e\u0026nbsp;Untrained\u0026nbsp;\u003cbr\u003e\u0026nbsp;Sex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training all n = 10\u003c/p\u003e\n \u003cp\u003eCON training all n = 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors,\u003cbr\u003e\u0026nbsp;knee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3, 2, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ed\u003c/sup\u003e (60, 90, 120, 150, 180, 210 \u0026deg;/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eMiller 2006\u0026nbsp;[105]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 38\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = F\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 17\u003cbr\u003e\u0026nbsp;CON training n = 21\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors, knee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e6, 4.5, 3, 20,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eMiller 2007\u0026nbsp;[72]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 20\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eStatus NR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = F\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 32\u003cbr\u003e\u0026nbsp;CON training n = 22\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eCollapsed elbow extensors and flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e6, 5, 3, 20,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eMoore 2012\u0026nbsp;[106]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 45 and 300\u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 60\u0026deg; elbow flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 22\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 9\u003cbr\u003e\u0026nbsp;CON training n = 9\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eElbow flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003eNR, NR, 2, 9,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 45\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eNickols-Richardson 2007\u0026nbsp;[73]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 20\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = F\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 33\u003c/p\u003e\n \u003cp\u003eCON training n = 37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eCollapsed knee extensors, flexors and\u003cbr\u003e\u0026nbsp;Collapsed elbow extensors and flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e6, 4.5, 3, 20,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eSato 2022\u0026nbsp;[107]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30 and 180 \u0026deg;/s\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 20, 55 and 90\u0026deg; elbow flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 22\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 13\u003cbr\u003e\u0026nbsp;CON training n = 13\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eElbow flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e1, 1, 5, 4,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 30\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eSeger 1998\u0026nbsp;[71]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30, 90 and 270\u0026deg;/s\u0026nbsp;\u003cbr\u003eMVC\u003csub\u003eISO\u003c/sub\u003e at 60\u0026deg; knee flexion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 25\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 10\u003cbr\u003e\u0026nbsp;CON training n = 10\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 4, 3, 10,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 90\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eSeger 2005\u0026nbsp;[70]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 30, 90, 270\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 25\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 5\u003cbr\u003e\u0026nbsp;CON training n = 5\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 4, 3, 10,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 90\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eSharma 2022\u0026nbsp;[108]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 26\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 15\u003c/p\u003e\n \u003cp\u003eCON training n = 15\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3, 2, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 60\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eTakayanagi 1995\u0026nbsp;[109]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60, 120, 180, 240\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 20\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 10\u003cbr\u003e\u0026nbsp;CON training n = 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors,\u003cbr\u003e\u0026nbsp;knee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 7, 3, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eTimmins 2016\u0026nbsp;[110]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 60 and 180\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 22\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eModerately trained\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex =M\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 14\u003cbr\u003e\u0026nbsp;CON training n = 14\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee flexors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e7, 5, 3, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ec\u003c/sup\u003e (60, 90\u0026deg;/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e9*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"9.649122807017545%\" valign=\"top\"\u003e\n \u003cp\u003eTomberlin 1991\u0026nbsp;[111]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.460526315789474%\" valign=\"top\"\u003e\n \u003cp\u003eMVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e at 100\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.214912280701753%\" valign=\"top\"\u003e\n \u003cp\u003emean age = 27\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eStatus NR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSex = MF\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eECC training n = 21\u003cbr\u003e\u0026nbsp;CON training n = 19\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.390350877192983%\" valign=\"top\"\u003e\n \u003cp\u003eKnee extensors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.87719298245614%\" valign=\"top\"\u003e\n \u003cp\u003e10, 3, 3, 6,\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVelocity 100\u0026deg;/s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.087719298245615%\" valign=\"top\"\u003e\n \u003cp\u003elow\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.320175438596491%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003eCON\u003c/em\u003e Concentric, \u003cem\u003eECC\u003c/em\u003e Eccentric, \u003cem\u003eF\u003c/em\u003e Female, \u003cem\u003eISO\u003c/em\u003e Isometric, \u003cem\u003eM\u003c/em\u003e Male, \u003cem\u003eMF\u003c/em\u003e mixed sex sample, \u003cem\u003eMVC\u003c/em\u003e Maximal Voluntary Contraction. \u003cem\u003eNR\u003c/em\u003e Not Reported, \u003cem\u003ecollapsed\u003c/em\u003e indicates the averaged MVC values for two muscle groups as an outcome\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003e The Physiotherapy Evidence Database scale results, assessing risk of bias (grade on the scale to 11)\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Template for Intervention Description and Replication completeness (grade on the scale to 11)\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec, d\u003c/sup\u003e Refers to training conditions where each set was performed at different velocities (\u003csup\u003ec\u003c/sup\u003e), or the velocity of training contractions changed from low to high or high to low throughout the training period (\u003csup\u003ed\u003c/sup\u003e)\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e Crossover study design where each participant was randomly assigned to a sequence of eccentric and concentric trainings (including a washout periods)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u0026nbsp;\u003c/strong\u003eSummarized study characteristics comparing changes in maximal voluntary concentric (MVC\u003csub\u003eCON\u003c/sub\u003e) and eccentric contraction (MVC\u003csub\u003eECC\u003c/sub\u003e) strength between eccentric and concentric training protocols\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"482\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\"\u003e\n \u003cp\u003e\u003cstrong\u003eSubgroup variable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\"\u003e\n \u003cp\u003e\u003cstrong\u003eCategory\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e\u003cstrong\u003en studies (outcomes\u003c/strong\u003e\u003csup\u003ea\u003c/sup\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e\u003cstrong\u003eoutcomes\u003c/strong\u003e\u003csup\u003ea\u003c/sup\u003e\u003cstrong\u003e\u0026nbsp;(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\"\u003e\n \u003cp\u003eOnly men\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e9 (24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eOnly women\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e7 (11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eMixed sample\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e11 (36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\" rowspan=\"4\"\u003e\n \u003cp\u003e\u003cstrong\u003eStatus\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\"\u003e\n \u003cp\u003eUntrained\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e5 (23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eModerately\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e18 (36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eTrained\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e1 (6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eNot reported\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e4 (6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\" rowspan=\"4\"\u003e\n \u003cp\u003e\u003cstrong\u003eMuscle\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003elower body\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\" valign=\"top\"\u003e\n \u003cp\u003eAll lower body\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e20 (56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eKnee extensors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e17 (37)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e66\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eKnee flexors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e3 (18)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e32\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eKnee flexors and extensors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e1 (1)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e2\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\" rowspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eMuscle\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eupper body\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\"\u003e\n \u003cp\u003eAll upper body\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e7 (15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eElbow flexors only\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e3 (6)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e40\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eElbow flexors and extensors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e2 (2)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e13\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eShoulder rotators\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e1 (6)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e40\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003e\u003cem\u003eShoulder abductors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e1 (1)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e\u003cem\u003e7\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.492723492723492%\" rowspan=\"4\"\u003e\n \u003cp\u003e\u003cstrong\u003eIsokinetic training to testing\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003evelocity\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;(\u0026deg;/s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.84823284823285%\" valign=\"top\"\u003e\n \u003cp\u003eLow to high\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.77962577962578%\"\u003e\n \u003cp\u003e8 (10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.87941787941788%\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eHigh to low\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e7 (10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eThe same\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e22 (25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"42.93478260869565%\"\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.69565217391305%\"\u003e\n \u003cp\u003e4 (26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.369565217391305%\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003e Number of comparisons between eccentric-only and concentric-only training results\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Training and testing at same isokinetic velocity\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u003c/sup\u003e Training at lower velocity than testing\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ed\u003c/sup\u003e training at higher velocity than testing\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ee\u003c/sup\u003e Velocity spectrum pyramidal ordering concept training\u003cstrong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3\u0026nbsp;\u003c/strong\u003eSummarized study characteristics comparing changes in maximal voluntary concentric (MVC\u003csub\u003eCON\u003c/sub\u003e), eccentric (MVC\u003csub\u003eECC\u003c/sub\u003e) and isometric (MVC\u003csub\u003eECC\u003c/sub\u003e) strength between eccentric and concentric training protocols\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"430\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eSubgroup variable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCategory\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003en studies (outcomes\u003c/strong\u003e\u003csup\u003ea\u003c/sup\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eoutcomes\u003c/strong\u003e\u003csup\u003ea\u003c/sup\u003e\u003cstrong\u003e\u0026nbsp;(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eOnly men\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5 (9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eOnly women\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 (5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMixed sample\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4 (6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eStatus\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eUntrained\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 (5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eModerately\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8 (14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNot reported\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1 (1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMuscle\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003elower body\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eAll lower body\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8 (15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e75\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eKnee extensors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e8 (13)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e87\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eKnee flexors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e1 (2)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e13\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMuscle\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eupper body\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAll upper body\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eElbow flexors\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e2 (4)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e80\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eShoulder abductors\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e1 (1)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e20\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eIsokinetic training\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003evelocity\u0026nbsp;\u003c/strong\u003e(\u0026deg;/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1 (1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5 (5)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 (3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eVelocity spectrum\u003csup\u003ea\u003c/sup\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1 (4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003e Number of comparisons between eccentric-only and concentric-only training results\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Velocity spectrum pyramidal ordering concept training\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"sports-medicine-open","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"smoa","sideBox":"Learn more about [Sports Medicine-Open](http://sportsmedicine-open.springeropen.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/smoa/default.aspx","title":"Sports Medicine-Open","twitterHandle":"@SpringerOpen","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"lengthening, shortening, muscle contraction, training mode, strength training specificity, resistance exercise","lastPublishedDoi":"10.21203/rs.3.rs-4385283/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4385283/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eConflicting results have been reported regarding the effects of resistance exercise training with eccentric (lengthening muscle) versus concentric (shortening muscle) contractions on changes in muscle mechanical function assessed by different contraction modes.\u003c/p\u003e\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eThe main objective of this systematic review with meta-analyses was to compare effectiveness of maximal isokinetic eccentric-only and concentric-only strength training for changes in maximal voluntary eccentric (MVC\u003csub\u003eECC\u003c/sub\u003e), concentric (MVC\u003csub\u003eCON\u003c/sub\u003e), and isometric contraction (MVC\u003csub\u003eISO\u003c/sub\u003e) strength in healthy adults.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe conducted a systematic search in PubMed, SPORTDiscus, and Google Scholar from February to March 2024 for studies that met the following criteria: (1) randomized controlled trials; (2) inclusion of eccentric-only and concentric-only strength training groups; (3) use of an isokinetic dynamometer for training and testing; (4) reporting changes over time in MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eECC\u003c/sub\u003e; and (5) using healthy adult participants. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. A multilevel random-effects model meta‑analyses with robust variance estimation were performed in Rstudio software using metaphor and clubSandwich packages. Moreover, sensitivity analysis was performed, excluding the highly influential studies. The potential moderating role of sex, training status and age of the participants, muscles, velocity in training and testing, initial MVC\u003csub\u003eECC\u003c/sub\u003e, MVC\u003csub\u003eCON\u003c/sub\u003e, and MVC\u003csub\u003eECC\u003c/sub\u003e/MVC\u003csub\u003eCON\u003c/sub\u003e ratio, and training-related variables such as number of repetitions per set, number of sets, number of sessions per week, and duration of the training protocol were also assessed.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eTwenty-seven studies matched with the criteria, and overall 162 study results were identified and included in the meta-analyses. Greater effects on MVC\u003csub\u003eECC\u003c/sub\u003e was found after eccentric-only versus concentric-only training (Hedge\u0026rsquo;s g: 1.51; 27% vs. 10%; p\u0026thinsp;\u0026lt;\u0026thinsp;.05). However, no differences were evident between the training modalities for changes in MVC\u003csub\u003eCON\u003c/sub\u003e (Hedge\u0026rsquo;s g: \u0026minus;\u0026thinsp;0.10; 13% vs. 14%, p\u0026thinsp;=\u0026thinsp;.726) and MVC\u003csub\u003eISO\u003c/sub\u003e (Hedge\u0026rsquo;s g: \u0026minus;\u0026thinsp;0.04; 18% vs. 17%; p\u0026thinsp;=\u0026thinsp;.923). The subgroup analyses showed smaller effect of eccentric-only than concentric-only training on MVC\u003csub\u003eCON\u003c/sub\u003e when eccentric-only training was performed at higher velocities than the velocities of MVC\u003csub\u003eCON\u003c/sub\u003e testing (Hedge\u0026rsquo;s g: \u0026minus;\u0026thinsp;0.99; p\u0026thinsp;\u0026lt;\u0026thinsp;.05). Meta-regressions showed that the longer the training period, the greater the superior effect of eccentric over concentric training on MVC\u003csub\u003eECC\u003c/sub\u003e.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eEccentric-only strength training is more effective for improving MVC\u003csub\u003eECC\u003c/sub\u003e, but both concentric-only and eccentric-only training provide similar effects on improving MVC\u003csub\u003eCON\u003c/sub\u003e and MVC\u003csub\u003eISO\u003c/sub\u003e. Further studies are necessary to investigate the mechanisms underpinning the superior effect of eccentric-only training.\u003c/p\u003e","manuscriptTitle":"Systematic review and meta-analysis of eccentric-only versus concentric-only strength training effects on maximal voluntary eccentric, concentric and isometric contraction strength","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-04 19:08:53","doi":"10.21203/rs.3.rs-4385283/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revision","date":"2025-04-05T08:52:23+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-05-20T18:49:44+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-20T07:04:27+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-08T05:24:52+00:00","index":"","fulltext":""},{"type":"submitted","content":"Sports Medicine-Open","date":"2024-05-07T17:45:16+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"sports-medicine-open","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"smoa","sideBox":"Learn more about [Sports Medicine-Open](http://sportsmedicine-open.springeropen.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/smoa/default.aspx","title":"Sports Medicine-Open","twitterHandle":"@SpringerOpen","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"fa82c8d6-b959-4159-a1d6-a3a9f41a0c66","owner":[],"postedDate":"June 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-25T16:36:06+00:00","versionOfRecord":{"articleIdentity":"rs-4385283","link":"https://doi.org/10.1186/s40798-025-00887-w","journal":{"identity":"sports-medicine-open","isVorOnly":false,"title":"Sports Medicine-Open"},"publishedOn":"2025-08-21 16:29:30","publishedOnDateReadable":"August 21st, 2025"},"versionCreatedAt":"2024-06-04 19:08:53","video":"","vorDoi":"10.1186/s40798-025-00887-w","vorDoiUrl":"https://doi.org/10.1186/s40798-025-00887-w","workflowStages":[]},"version":"v1","identity":"rs-4385283","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4385283","identity":"rs-4385283","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}