Comparing the acute effects of diagonal mobilization and Nordic hamstring curls on the vertical jump performances, static and dynamic balance, and landing stabilization in youth soccer players: a randomized multi-arm study design

Comparing the acute effects of diagonal mobilization and Nordic hamstring curls on the vertical jump performances, static and dynamic balance, and landing stabilization in youth soccer players: a randomized multi-arm study design | 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 Comparing the acute effects of diagonal mobilization and Nordic hamstring curls on the vertical jump performances, static and dynamic balance, and landing stabilization in youth soccer players: a randomized multi-arm study design Rafał Studnicki, Urszula Tomaszewicz, Rita Hansdorfer-Korzon, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4365729/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background Ensuring the utilization of appropriate techniques that maximize soccer performance in terms of force, muscular power, balance, and stabilization is crucial for mitigating injury risk. Aim: The objective of this study was to compare the effects of diagonal mobilization (DM), Nordic hamstring curls (NHC), and placebo on vertical jump force and power outcomes, as well as static and dynamic balance assessed through unilateral tests, along with time to stabilization and force during landing tests conducted among young soccer players. Methods: A randomized multi-arm study design was employed. Seventy-five young male soccer players participated in this study, with an average age of 13.9 years (± 0.9), height of 174.4 cm (± 8.1), and weight of 60.6 kg (± 8.9). Participants were randomly assigned to one of three groups and were assessed both before and after the intervention. The assessment included tests such as the countermovement jump (CMJ), squat jump (SJ), single-leg standing (SLS), single-leg hold (SLLH), and the land and hold test (LH), all conducted on a force platform. Results: Significant interactions time × group were found in CMJ height ( p = 0.011; \({\eta }_{p}^{2}\) <0.118), CMJ peak landing force ( p =0.007; \({\eta }_{p}^{2}\) =0.129), CMJ peak power ( p = 0.101; \({\eta }_{p}^{2}\) =0.062), and SJ concentric peak power ( p = 0.034; \({\eta }_{p}^{2}\) =0.090). Moreover, SLS CP range anterior-posterior ( p = 0.011; \({\eta }_{p}^{2}\) =0.118), SLLH time to stabilization ( p <0.001; \({\eta }_{p}^{2}\) =0.299), SLLH peak drop landing force ( p <0.001; \({\eta }_{p}^{2}\) =0.186), LH time to stabilization ( p = 0.032; \({\eta }_{p}^{2}\) =0.041) and LH peak drop landing force ( p = 0.012; \({\eta }_{p}^{2}\) =0.116). The between-group analysis showed that the placebo group exhibited significantly greater CMJ landing force compared to the DM group in the post-intervention phase (p<0.001). Additionally, the placebo group exhibited significantly smaller SJ concentric peak power compared to the DM group in the post-intervention phase (p < 0.001). The placebo group exhibited significantly greater CP medial-lateral (p=0.023) and CP anterior-posterior (p=0.006) compared to the DM group in the post-intervention phase. Also, placebo presented significantly greater CP medial-lateral (p=0.036) and CP anterior-posterior (p = 0.004) compared to the NHC group. Conclusions: In conclusion, DM revealed significant effectiveness in enhancing landing forces during both CMJ and SJ, while also improving static and dynamic balance parameters compared to the placebo. Although it did not show significant superiority to NHC in most parameters, DM exhibited significant superiority over NHC during the LH. DM appears to be a promising and effective approach for enhancing performance and minimizing injury risk parameters in soccer players. football musculoskeletal manipulations postural balance biomechanics Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction In soccer, the relationship between muscle force, power, and balance is paramount for player performance and injury prevention [ 1 ]. Enhanced muscle force and power directly correlate with improved sprinting speed, jumping ability, and agility, all essential components of soccer performance [ 2 ]. Studies [ 3 ] have consistently demonstrated that stronger and more powerful lower limb muscles enable players to generate greater force during explosive movements such as sprinting, jumping, and tackling, leading to increased acceleration and higher jump heights. Static and dynamic balance, meanwhile, are integral aspects of soccer performance and injury risk [ 4 ]. Static balance, characterized by the ability to maintain stability and equilibrium during stationary positions, is crucial to exhibit better control and improving their ability to react quickly to changes in game dynamics [ 5 , 6 ]. Dynamic balance, on the other hand, involves the capacity to maintain stability and control while in motion, enabling players to performance complex movements [ 7 ]. Studies have highlighted the importance of dynamic balance in reducing the risk of injury by enhancing neuromuscular coordination and proprioception [ 8 ], which are vital for injury prevention mechanisms such as landing stability and joint protection during high-impact activities like sudden direction changes and tackles [ 9 , 10 ]. In soccer, where explosive movements like jumping occurs repeatedly, the implementation of suitable warm-up strategies is crucial for injury prevention and optimal performance [ 11 ]. Appropriate warm-up routines enhance neuromuscular activation and proprioception, priming the player’s body for the demands of explosive movements as jumping and subsequent landings [ 12 ]. By incorporating appropriate warm-up strategies, players may improve their ability to cope with landing forces during jumps [ 13 ]. These exercises may also enhance dynamic and static balance, as well as the time to stabilization after jumps, which are essential components in mitigating injury risk during high-intensity movements. One approach to improving immediate strength and preparedness in young soccer players is through diagonal manual mobilization (DM), as suggested by research [ 14 ]. DM involves manually manipulating joints in the lower limbs, which has been suggested to boost joint flexibility, proprioception, and neuromuscular excitability. These effects may help optimize muscle function for better performance [ 15 ]. Previous reports in healthy adults revealed that manual therapy techniques were effective in improving posture, which can be related to balance enhancement [ 16 ]. Moreover, a single session of joint mobilization significantly improved one leg balance and timed up and go performance in adults compared to placebo [ 17 ]. Also in sports, recent studies on young soccer players have highlighted the positive impact of tissue mobilization on different facets of athletic ability and reducing of injury risk [ 18 ]. Despite the aforementioned preliminary findings, research on the utilization of DM in sports, particularly in soccer, is scarce. Understanding how DM can enhance acute effects on muscle force and power, as well as static and dynamic balance, holds particular significance. This is especially true in circumstances where specific imbalances or player needs necessitate tailored strategies to mitigate the risk of injury. Furthermore, comparing DM with alternative approaches, such as those centered on specific exercises, is of notable interest. For instance, Nordic curl exercises directly target the hamstring muscles, potentially bolstering eccentric strength and muscle activation [ 19 ]. Studies have shown that performing eccentric exercises like the Nordic curl can heighten muscle activation and prime subsequent muscle contractions [ 20 ]. While Nordic hamstring curls (NHC) primarily focus on the hamstrings, they also involve other muscles in the posterior chain, including the glutes and lower back. Although they may not directly address balance or landing forces in jumps, they can indirectly contribute to the enhancement of these aspects. Exploring how various strategies, such as DM or NHC, can contribute to enhancing soccer players' performance in terms of muscle force and power, as well as static and dynamic balance, while also reducing landing forces, is of significant interest to practitioners. However, research in this area is lacking, necessitating a deeper analysis to understand the effectiveness of these strategies. Therefore, the aim of this study was to compare the effects of DM, NHC, and a placebo on vertical jump force and power outcomes, as well as static and dynamic balance assessed through unilateral tests. Additionally, the study assessed time to stabilization and force during landing tests conducted among young soccer players. We hypothesize that DM and NHC may yield significantly greater benefits than a placebo on the observed measures. Methods Study design The research methodology adopted a randomized controlled design in which DM and NHC were compared with a placebo group. This design secured against bias by keeping both participants and evaluators unaware of who received the intervention. Prior to the initial assessment, randomization took place to conceal allocation, utilizing a simple randomization method enabled by a research randomizer website. The allocation ratio was 1:1. To ensure blinding process, evaluators remained uninformed about participants' group assignments throughout the study. The intervention protocol consisted of a single session. Participants in the DM group received manual therapy, while those in the placebo group underwent a simulated intervention. In the NHC group, an instructor administered a Nordic exercise intervention. Ethics Approval for the study was granted by the Independent Bioethics Committee for Scientific Research at the Medical University of Gdańsk (approval dated July 7, 2023, Resolution No. NKBBN 392/2023), in conjunction with the AZS Central Academic Sports Center in Gdańsk. Participants were thoroughly briefed on the study's objectives and procedures, with a detailed explanation of the study protocol provided. Written consent was obtained from either the parent or legal guardian before participants' involvement. The study strictly followed the ethical guidelines for human research as outlined in the Declaration of Helsinki. Participants Prior to the commencement of the study, a sample size calculation was performed using G*power software (version 3.1.9.6., Universität Düsseldorf, Germany). The calculation aimed for a statistical power of 0.85 within a two-group ANOVA repeated measures design, accounting for two evaluations, within-between interaction, an effect size of 0.2 (small), and a significance level of 0.05. This analysis yielded a recommended sample size of 72 participants. Participants were recruited from the Varsovia Football Academy, a member of the Central Junior League, utilizing convenience sampling. Initially, 76 potential participants were identified and screened for eligibility based on the following criteria: (i) aged between 13 to 15 years old, engaged in regular soccer practice; (ii) absence of lower limb and lumbar spine surgery or injuries within the last 6 months (hip, knee, ankle), no current pain in the hip, knee, or ankle joints, no hypermobility of the lower limb joints, and no history of neurological or connective tissue disorders; and (iii) availability for both assessment time points. Following the exclusion of one participant due to recent injuries within the last month, a total of 75 eligible participants remained for random assignment to study groups (Fig. 1 ). <<>> Training intervention Diagonal mobilization To provide context, a single intervention session was conducted with participants, following a pre-intervention evaluation and immediately followed by a post-intervention assessment. These interventions occurred on the same day of the week, with a preceding 48-hour rest period to ensure consistency and replicability. Participants underwent an active intervention known as DM, involving passive rhythmic gliding mobilization. Before commencement, participants received verbal instructions about the intervention. DM, designed to enhance planned mobility through three-dimensional movements, was administered by a qualified physiotherapist with 25 years of experience in manual therapy. The intervention was consistently performed by the same therapist. The procedure began with the participant lying supine, with the upper limbs positioned alongside the torso. The therapist initiated mobilization of the knee joint by gently moving the proximal tibia to enhance internal rotation (medially, cranially, dorsally). In the prone position, mobilization of the hip joint involved gently moving the femoral head (ventrally, medially, cephalad), while mobilization of the sacroiliac joint included gently moving the sacrum to improve nutation (ventrally, cephalad, laterally). Each movement progressed to stage II until tissue tension was palpated, indicating the achievement of tissue tension and subsequent release. The therapist ensured the participant's comfort throughout and conducted mobilization for 2 minutes. This therapeutic protocol was administered once per subject, resulting in a total therapy time of 6 minutes. Nordic Hamstring curl Before commencing the study, all participants underwent familiarization with the exercise program. The eccentric hamstring exercise protocol involved executing Nordic hamstring curls against resistance. Participants assumed a kneeling position on the mat and were instructed on proper execution, emphasizing the importance of keeping their arms aligned along their torso to ensure safe landing and maintaining straight backs and hips throughout the movement. Additionally, participants were advised to promptly report any muscle cramps to mitigate the risk of potential strains during exercise. Each volunteer completed three trial runs. The exercise regimen comprised two sets of 8 repetitions each, with a rest interval of 60 seconds between sets. Throughout the entirety of the exercise session, the instructor closely monitored the participants' execution to ensure proper form and technique. Placebo The placebo intervention followed a comparable procedure: participants received verbal instructions, and the intervention occurred in the same position and timeframe as the active mobilization. To mimic real mobilization, the therapist positioned their hands on the same points of contact, employing minimal movement (1st degree). Both active and placebo interventions had a duration of eight minutes [ 21 ]. Assessment procedures The assessments occurred 5 minutes before and after the intervention process, all on the same day, within a quiet room maintained at a temperature of 23ºC with a relative humidity of 55%, regulated by an air conditioner. Initially, demographic and anthropometric data were collected from the participants. Following this, participants received a detailed oral explanation of the study procedure. A preliminary attempt at performing the test, without recording results, was permitted. The limb chosen for assessment was determined randomly using a "coin toss" method. Two members of the research team supervised the tests, paying close attention to changes in torso and pelvic posture during both landing and standing on one leg [ 22 ]. Furthermore, they ensured adherence to the testing sequence and offered verbal encouragement to the volunteers throughout the tests. The collected data were uploaded to a digital platform. The sequence of assessments remained consistent for all participants, commencing with single leg standing (SLS), followed by single leg bend and hold (SLLH), Countermovement Jump Testing (CJT), Squat test (ST), and Jump Testing (JT). Single leg standing (SLS) Participants initiated the evaluation by standing on force plates (ForceDecks, VALD, Brisbane, Australia) in a standard standing posture. With arms by their sides and their gaze fixed forward, participants were instructed to maintain complete stillness for 2–3 seconds after lifting the other limb. This process was repeated three times, with a 30-second break between each repetition. The resulting data included center of pressure (CP) range in both anterior-posterior (mm) and medial-lateral (mm) directions, as well as mean velocity (mm/s), computed using the VALD ForceDecks software [ 23 ]. The average of the three attempts was used for subsequent data analysis [ 28 ]. Single leg lend and hold (SLLH) Participants initiated the evaluation by standing on force plates (ForceDecks, Vald Performance, Brisbane, Australia), positioned 30 cm in front of them. They stood with their feet together, hands on hips, and gaze fixed straight ahead. Each participant was instructed to maintain complete stillness for 2–3 seconds before each jump. Following this, the instructor directed the participant to execute a single-leg jump and maintain the position until prompted, with the resulting duration recorded (minimum 3 seconds). This sequence was repeated three times, with a 30-second break between each repetition. The collected data included time to stabilization (s) and peak drop landing force (N), which were calculated using the VALD ForceDecks software [ 23 ]. The average of the three attempts was utilized for subsequent data analysis [ 29 ]. Countermovement Jump Testing (CJT) The participant began from a standard standing position on the research platform, with hands on hips and gaze fixed straight ahead. They were instructed to maintain complete stillness for 2–3 seconds both before and between each jump. The instructor then directed the participant to execute a two-legged jump, aiming to achieve maximum height. This process was repeated three times. Outcome variables obtained included jump height, peak power and peak landing force, computed using the VALD ForceDecks software. The final mean strength variables utilized for analysis were the average values derived from the three jumps performed [ 28 ]. Squat test (ST) Participants performed an unloaded squat with maximum range of motion on ForceDecks force plates (Vald Performance, Brisbane, Australia), while maintaining a straight torso position. Although participants were instructed to adopt their usual comfortable foot position, the width between their feet was measured to ensure consistent positioning for subsequent examinations. Athletes were instructed to complete three repetitions, with a 30-second rest interval between each repetition. The results obtained from each trial included peak force (N), maximum negative displacement (cm), and concentric peak power per body mass (W/kg). The trial producing the average maximum force, as calculated by the VALD ForceDecks software, was selected for statistical analysis. Lend and hold (LH) The participant began the study by standing on ForceDecks force plates (VALD, Brisbane, Australia) in a normal standing position. The participant stood with arms alongside the torso and gaze fixed straight ahead. The participant was instructed to remain completely still for 2–3 seconds before and between each jump. The instructor then directed the participant to perform a two-legged jump to jump as high as possible. This procedure was repeated three times. The resulting data included Time to Stabilization (s) and Peak Drop Landing Force (N), calculated by the VALD ForceDecks software. The final variables for mean force used for analysis were the calculated average values from the three jumps performed. Statistical procedures After investigating potential outliers, descriptive statistics were presented, utilizing means and standard deviations. Before proceeding to inferential statistics, the normality of the sample underwent evaluation, and it was confirmed through the Kolmogorov-Smirnov test (p > 0.05). Similarly, the assumption of homogeneity was validated via Levene’s test (p > 0.05). Given the study's design (two assessments for three groups), a mixed ANOVA was utilized to examine interactions between time and groups. This analysis also involved the calculation of partial eta squared ( \({\eta }_{p}^{2}\) ). Furthermore, post-hoc comparisons were conducted using the Bonferroni test. All statistical analyses were carried out using JASP software (version 0.18.3, University of Amsterdam, The Netherlands), with a predetermined significance level of p < 0.05. RESULTS Seventy-five young male soccer players, averaging 13.9 years of age (± 0.9), participated in this study. On average, they stood at 174.4 cm tall (± 8.1) and weighed 60.6 kg (± 8.9). These participants are affiliated with a regional-level soccer club, engaging in three training sessions per week in addition to matches. After random allocation to each group, the following are the main characteristics for each group: DM (N = 25; mean age 13.7 years ± 0.8; height 170.9 cm ± 8.5; weight 55.5 kg ± 6.5); NHC (N = 25, mean age 14.2 years ± 0.9; height 175.6 cm ± 7.1; weight 64.0 kg ± 9.1); and placebo (N = 25; mean age 13.9 years ± 0.9; height 174.4 cm ± 8.1; weight 60.6 kg ± 8.9). Table 1 shows the descriptive statistics of the outcomes associated with CMJ and SJ performance before and after the interventions. Significant interactions time × group were found in CMJ height ( F 2,72 =4.800; p = 0.011; \({\eta }_{p}^{2}\) <0.118), CMJ peak landing force ( F 2,72 =5.351; p =0.007; \({\eta }_{p}^{2}\) =0.129), CMJ peak power ( F 2,72 =2.362; p =0.101; \({\eta }_{p}^{2}\) =0.062), and SJ concentric peak power ( F 2,72 =3.540; p = 0.034; \({\eta }_{p}^{2}\) =0.090). Table 1 Descriptive statistics (mean ± standard deviation) of the outcomes associated with CMJ and SJ performance before and after the interventions. DM (n = 25) NHC (n = 25) Placebo (n = 25) Between-group analysis CMJ height (cm) Pre 18.6 ± 4.5 18.5 ± 4.0 18.5 ± 4.2 F 2,72 =0.005; p = 0.995; \({\eta }_{p}^{2}\) <0.001 Post 21.0 ± 6.4 17.8 ± 4.5 17.5 ± 4.2 F 2,72 =3.624; p = 0.032*; \({\eta }_{p}^{2}\) =0.091 CMJ peak landing force (N) Pre 1588.7 ± 582.2 1691.3 ± 661.5 1681.4 ± 509.3 F 2,72 =0.232; p = 0.794; \({\eta }_{p}^{2}\) =0.006 Post 1414.8 ± 584.5 1687.1 ± 554.2 2047.3 ± 611.2 F 2,72 =7.385; p = 0.001*; \({\eta }_{p}^{2}\) =0.170 CMJ peak power (W/kg) Pre 36.4 ± 5.0 35.9 ± 5.0 35.7 ± 4.7 F 2,72 =0.129; p = 0.879; \({\eta }_{p}^{2}\) =0.004 Post 38.1 ± 6.6 35.6 ± 4.9 34.9 ± 5.2 F 2,72 =2.217; p = 0.116; \({\eta }_{p}^{2}\) =0.058 SJ peak force (N) Pre 486.5 ± 118.4 533.5 ± 114.8 557.2 ± 120.6 F 2,72 =2.323; p = 0.105; \({\eta }_{p}^{2}\) =0.061 Post 534.9 ± 144.8 560.4 ± 144.9 521.4 ± 156.3 F 2,72 =0.442; p = 0.645; \({\eta }_{p}^{2}\) =0.012 SJ maximum negative displacement (cm) Pre −36.5 ± 7.2 −35.3 ± 7.3 −33.3 ± 7.4 F 2,72 =1.252; p = 0.292; \({\eta }_{p}^{2}\) =0.034 Post −37.1 ± 5.1 −34.2 ± 8.5 −37.4 ± 8.6 F 2,72 =1.372; p = 0.260; \({\eta }_{p}^{2}\) =0.037 SJ concentric peak power (W/kg) Pre 8.0 ± 1.6 7.2 ± 1.8 8.0 ± 1.9 F 2,72 =1.500; p = 0.230; \({\eta }_{p}^{2}\) =0.040 Post 9.2 ± 1.9 8.1 ± 2.2 6.9 ± 1.9 F 2,72 =7.730; p < 0.001*; \({\eta }_{p}^{2}\) =0.177 DM: diagonal mobilization group; NHC: Nordic hamstring curl; CMJ: countermovement jump; SJ: squat jump; *: significantly different at p < 0.05. <<>> Table 2 shows the descriptive statistics of the outcomes associated with SLS, SLLH and LH performance before and after the interventions. SLS CP range anterior-posterior ( F 2,72 =4.805; p = 0.011; \({\eta }_{p}^{2}\) =0.118), SLLH time to stabilization ( F 2,72 =15.391; p <0.001; \({\eta }_{p}^{2}\) =0.299), SLLH peak drop landing force ( F 2,72 =8.237; p <0.001; \({\eta }_{p}^{2}\) =0.186), LH time to stabilization ( F 2,72 =3.608; p =0.032; \({\eta }_{p}^{2}\) =0.041) and LH peak drop landing force ( F 2,72 =4.711; p =0.012; \({\eta }_{p}^{2}\) =0.116). However, no significant interactions were found in SJ peak force ( F 2,72 =2.317; p =0.106; \({\eta }_{p}^{2}\) =0.060), SJ maximum negative displacement ( F 2,72 =2.230; p = 0.115; \({\eta }_{p}^{2}\) =0.058), SLS CP range media-lateral ( F 2,72 =1.760; p =0.179; \({\eta }_{p}^{2}\) =0.047), and SLS mean velocity ( F 2,72 =0.163; p = 0.850; \({\eta }_{p}^{2}\) =0.005). Table 2 Descriptive statistics (mean ± standard deviation) of the outcomes associated with CMJ and SJ performance before and after the interventions. DM (n = 25) NHC (n = 25) Placebo (n = 25) Between-group analysis SLS CP range media-lateral (mm) Pre 30.4 ± 7.2 28.4 ± 5.1 32.4 ± 5.7 F 2,72 =2.667; p = 0.076; \({\eta }_{p}^{2}\) =0.069 Post 29.6 ± 6.4 29.9 ± 5.9 34.4 ± 6.1 F 2,72 =4.738; p = 0.012*; \({\eta }_{p}^{2}\) =0.116 SLS CP range anterior-posterior (mm) Pre 48.0 ± 21.9 47.4 ± 17.2 56.6 ± 19.2 F 2,72 =1.760; p = 0.179; \({\eta }_{p}^{2}\) =0.047 Post 49.2 ± 13.0 48.7 ± 17.2 64.2 ± 19.0 F 2,72 =7.053; p = 0.002*; \({\eta }_{p}^{2}\) =0.164 SLS mean velocity (mm/s) Pre 55.8 ± 17.0 55.5 ± 18.6 62.8 ± 19.3 F 2,72 =1.303; p = 0.278; \({\eta }_{p}^{2}\) =0.035 Post 50.8 ± 13.0 55.0 ± 13.8 48.1 ± 16.5 F 2,72 =1.424; p = 0.247; \({\eta }_{p}^{2}\) =0.038 SLLH time to stabilization (s) Pre 0.54 ± 0.18 0.44 ± 0.16 0.43 ± 0.16 F 2,72 =2.996; p = 0.056; \({\eta }_{p}^{2}\) =0.077 Post 0.37 ± 0.11 0.42 ± 0.17 0.49 ± 0.18 F 2,72 =3.970; p = 0.023*; \({\eta }_{p}^{2}\) =0.099 SLLH peak drop landing force (N) Pre 827.2 ± 189.8 824.3 ± 153.8 937.2 ± 198.8 F 2,72 =3.129; p = 0.050; \({\eta }_{p}^{2}\) =0.080 Post 856.9 ± 317.4 863.7 ± 246.2 1168.2 ± 314.9 F 2,72 =9.100; p < 0.001*; \({\eta }_{p}^{2}\) =0.202 LH time to stabilization (s) Pre 0.51 ± 0.15 0.51 ± 0.15 0.45 ± 0.12 F 2,72 =1.551; p = 0.219; \({\eta }_{p}^{2}\) =0.041 Post 0.43 ± 0.13 0.53 ± 0.18 0.51 ± 0.13 F 2,72 =3.491; p = 0.036*; \({\eta }_{p}^{2}\) =0.088 LH peak drop landing force (N) Pre 1278.1 ± 584.7 1534.8 ± 367.1 1660.2 ± 488.3 F 2,72 =3.979; p = 0.023; \({\eta }_{p}^{2}\) =0.100 Post 1081.6 ± 345.6 1469.5 ± 602.5 1915.0 ± 590.9 F 2,72 =15.685; p < 0.001*; \({\eta }_{p}^{2}\) =0.303 DM: diagonal mobilization group; NHC: Nordic hamstring curl; SLS: single leg standing test; SLLH: single leg lend and hold test; LH: Lend and hold test; CP: center of pressure; *: significantly different at p < 0.05. <<>> Figure 2 shows both between-group and within-group descriptive statistics regarding the outcomes of the CMJ test. The between-group analysis showed that the placebo group exhibited significantly greater CMJ landing force compared to the DM group in the post-intervention phase (632.5 N; p < 0.001). Within-group analysis revealed that the DM group experienced a significant improvement in CMJ height (2.4 cm; p = 0.007), whereas the placebo group demonstrated a significant increase in CMJ landing force (365.9 N; p = 0.003) following the intervention. <<>> Figure 3 shows both between-group and within-group descriptive statistics regarding the outcomes of the SJ test. The between-group analysis showed that the placebo group exhibited significantly smaller SJ concentric peak power compared to the DM group in the post-intervention phase (2.3 W/kg; p < 0.001). Within-group analysis revealed that the DM group experienced a significant increase in SJ concentric peak power (1.2 W/kg; p = 0.006), whereas the placebo group demonstrated a significant increase in SJ maximum negative displacement (4.1 cm; p = 0.024) and decrease in SJ concentric peak power (1.1 W/kg; p = 0.0013) following the intervention. The NHC group significantly increased SJ concentric peak power after the intervention (0.9 W/kg; p = 0.045). <<>> Figure 4 shows both between-group and within-group descriptive statistics regarding the outcomes of the SLS test. The between-group analysis showed that the placebo group exhibited significantly greater CP medial-lateral (4.8 mm; p = 0.023) and CP anterior-posterior (15.0 mm; p = 0.006) compared to the DM group in the post-intervention phase. Also, placebo presented significantly greater CP medial-lateral (4.5 mm; p = 0.036) and CP anterior-posterior (15.5 mm; p = 0.004) compared to the NHC group. Within-group analysis revealed that the placebo group experienced a significant increase in CP anterior-posterior (7.6 mm; p = 0.030), whereas the demonstrated a significant decrease in mean velocity (14.7 mm/s; p < 0.001). <<>> Figure 5 shows both between-group and within-group descriptive statistics regarding the outcomes of the SLLH and LH tests. The between-group analysis showed that the placebo group exhibited significantly greater SLLH time to stabilization (0.12s; p = 0.019) and SLLH peak landing force (311.3N; p = 0.001) and LH peak landing force (833.4 N; p < 0.001) compared to the DM group in the post-intervention phase. Moreover, placebo also presented significantly greater SLLH peak landing force compared to NHC group (304.5 N; p = 0.001). Considering the LH peak landing force, NHC had significantly greater values than DM (445.5 N; p = 0.033). Within-group analysis revealed that the DM group experienced a significant decrease in SLLH time to stabilization (0.17 s; p < 0.001), and LH time to stabilization (0.08 s; p = 0.034) after the intervention. On the other hand, placebo group experienced a significantly increase in SLLH peak landing force (231.0 N; p < 0.001) and LH peak landing force (254.8 N; p = 0.020). <<>> Discussion Our study revealed that the DM group exhibited significant improvements in several key outcomes compared to the placebo group. Specifically, participants in the DM group showed enhancements in CMJ landing force, SJ concentric peak power, balance in both anterior-posterior and medial-lateral center of pressure, time to stabilization in the SLLH test, and peak landing force in both SLLH and LH tests. When comparing the DM group to the NHC group, no significant differences were observed across most variables. However, it is worth noting that the DM group displayed significantly better results than the NHC group in terms of LH peak landing force. Manual therapy focused on DM significantly enhanced static balance in the anterior-posterior and medial-lateral center of pressure during the SLS test, possibly being justified be some underlying mechanisms. DM techniques targeted specific muscle groups and joint structures in lower limbs, possibly promoting proprioceptive feedback and neuromuscular control [ 24 ]. By applying manual forces diagonally across the region, these techniques may engage sensory receptors within muscles, tendons, and ligaments, eliciting proprioceptive signals that enhance the brain's awareness of limb position and movement [ 25 ]. This heightened proprioception allows for more precise adjustments in muscle activation and joint positioning, crucial for maintaining balance during single-leg stance [ 26 ]. Furthermore, DM can modulate neural pathways involved in postural control [ 27 ]. Research suggests that manual therapy techniques, including mobilization, can influence the excitability of neural circuits within the central nervous system, particularly those related to balance and coordination [ 28 ]. Our results also found that DM significantly improved the time to stabilization in the SLLH and LH tests, possibly also justified by eliciting proprioceptive feedback that enhances neuromuscular control and coordination. For example, a study by Espí-López et al [ 29 ] found that manual therapy techniques, including mobilization, led to increased dynamic balance possibly due enhancing proprioceptive ability. Also, research has shown that manual therapy techniques can influence cortical excitability and spinal reflex arcs, leading to enhanced motor output and coordination [ 30 ]. For instance, a study by Lehr et al [ 31 ] revealed that mobilization with movement significantly enhanced dynamic balance in health individuals. By possibly improving proprioceptive input, diagonal mobilization facilitates more precise adjustments in muscle activation and joint positioning, which are essential for stabilizing the body during dynamic tasks like the SLLH and LH tests. Additionally, manual therapy interventions can modulate neural pathways involved in motor control and balance [ 32 ]. Our results also revealed that DM significantly improve landing force in the SLLH and LH tests, and CMJ. Although similar studies investigating this phenomenon have not been observed, a previous study revealed that high-impact landing forces were reduced through the implementation of augmented feedback information instructing individuals on proper landing techniques [ 33 ]. In our case, DM may have acted as a regulator of proprioception, facilitating improved coordination of muscle activity, thereby reducing excessive landing forces and promoting smoother force absorption. Additionally, by targeting joint restrictions and asymmetries, manual therapy techniques optimize the alignment of the kinetic chain, thereby reducing the risk of excessive loading and injury during landing tasks. Research has shown that manual therapy interventions can improve joint range of motion and biomechanical alignment. For example, a study by Stanek et al [ 34 ] found that manual therapy techniques improved tibial range of motion. These biomechanical improvements can enhance the ability to absorb and distribute forces during landing, resulting in reduced landing forces and improved landing mechanics. While our study revealed promising results regarding the effectiveness of DM in improving various outcomes related to balance, neuromuscular control, and landing force, several limitations should be acknowledged. Firstly, our sample size was exclusively related with youth players, limiting the generalizability of our findings to elite populations. Future research should aim to test these findings with elite players aiming to ensure the robustness of the observed effects. Furthermore, despite our efforts to introduce a gentle approach in the control group to mimic a placebo effect, it may not effectively evoke the placebo response. This limitation is noteworthy, particularly in manual therapy, where the identification and implementation of placebos are not as straightforward as in other clinical trials. Additionally, the lack of a long-term follow-up assessment in our study prevents us from understanding the durability of the improvements seen with DM over time. Longitudinal studies are warranted to evaluate the sustained effects of DM interventions beyond the immediate post-treatment period. Furthermore, the mechanisms underlying the observed improvements with DM remain speculative and warrant further investigation. Incorporating neurophysiological assessments, such as electromyography or functional MRI, could elucidate the neurobiological mechanisms through which DM influences balance and neuromuscular control. Additionally, exploring the optimal dosage and frequency of DM interventions could help optimize treatment protocols for maximal effectiveness. Despite these limitations, our study provides valuable insights into the potential benefits of DM in improving balance and neuromuscular function, laying the groundwork for future research to address these gaps and refine our understanding of its therapeutic mechanisms and clinical applications. From a clinical perspective, our findings indicate that DM can be integrated by practitioners to augment several performance parameters in young soccer players. These include enhanced landing force in CMJ, increased concentric peak power in SJ, and improvements in balance metrics such as anterior-posterior and medial-lateral center of pressure. Notably, DM should be applied cautiously, tailored to individual player needs to address specific imbalances. Furthermore, in the context of return-to-play scenarios, the incorporation of DM may offer additional benefits, potentially mitigating injury risks before training sessions or matches. Conclusions The study findings revealed the significant benefits of DM in improving various key outcomes compared to a placebo group, particularly evident in enhancements in CMJ landing force, SJ concentric peak power, and balance metrics such as anterior-posterior and medial-lateral center of pressure. Additionally, DM resulted in significant improvements in time to stabilization during specific tests, indicating enhanced neuromuscular control. Despite these promising results, the study acknowledges limitations related to the sample selected (youth players) and the lack of information about the longitudinal extension of the effects, underscoring the need for future research to validate findings across diverse populations and investigate underlying mechanisms through neurophysiological assessments. Nonetheless, this study suggests that DM can be particularly beneficial for athletes requiring individualized therapeutic interventions prior to training or matches, especially for improving balance and movement control, thereby potentially mitigating injury risk factors. Declarations Ethics Approval and Consent to participate. Approval for the study was granted by the Independent Bioethics Committee for Scientific Research at the Medical University of Gdańsk (approval dated July 7, 2023, Resolution No. NKBBN 392/2023), in conjunction with the AZS Central Academic Sports Center in Gdańsk. Participants were thoroughly briefed on the study's objectives and procedures, with a detailed explanation of the study protocol provided. Written consent was obtained from either the parent or legal guardian before participants' involvement. The study strictly followed the ethical guidelines for human research as outlined in the Declaration of Helsinki. Acknowledgments The authors have no acknowledgments. Author contributions RS – conception, performance of work, interpretation or analysis of data, preparation of the manuscript, revision for important intellectual content. UT – performance of work, preparation of the manuscript, revision for important intellectual content RHK – performance of work, preparation of the manuscript, revision for important intellectual content AK – performance of work, preparation of the manuscript, revision for important intellectual content Competing Interest The authors declare that they have no competing interests. Consent for publication. Not applicable Availability of Data and Material The data is secured and only co-authors have access to it. Data are available from the corresponding author upon request Funding The authors report no funding References Ergen E, Ulkar B. Proprioception and Ankle Injuries in Soccer. Clin Sports Med. 2008;27:195–217. Peñailillo L, Espíldora F, Jannas-Vela S, Mujika I, Zbinden-Foncea H. Muscle Strength and Speed Performance in Youth Soccer Players. J Hum Kinet. 2016;50:203–10. Suchomel TJ, Nimphius S, Stone MH. The Importance of Muscular Strength in Athletic Performance. 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Sports Health: Multidisciplinary Approach. 2021;13:181–6. Gómez F, Escribá P, Oliva-Pascual-Vaca J, Méndez-Sánchez R, Puente-González AS. Immediate and Short-Term Effects of Upper Cervical High-Velocity, Low-Amplitude Manipulation on Standing Postural Control and Cervical Mobility in Chronic Nonspecific Neck Pain: A Randomized Controlled Trial. J Clin Med. 2020;9:2580. Prior S, Mitchell T, Whiteley R, O’Sullivan P, Williams BK, Racinais S, et al. The influence of changes in trunk and pelvic posture during single leg standing on hip and thigh muscle activation in a pain free population. BMC Sports Sci Med Rehabil. 2014;6:13. Wrona HL, Zerega R, King VG, Reiter CR, Odum S, Manifold D, et al. Ability of Countermovement Jumps to Detect Bilateral Asymmetry in Hip and Knee Strength in Elite Youth Soccer Players. Sports. 2023;11:77. Clark NC, Röijezon U, Treleaven J. Proprioception in musculoskeletal rehabilitation. Part 2: Clinical assessment and intervention. Man Ther. 2015;20:378–87. Joshua AM, Karthikbabu S. Therapeutic Approaches. Physiotherapy for Adult Neurological Conditions. Singapore: Springer Nature Singapore; 2022. pp. 31–183. Ageberg E, Roberts D, Holmström E, Fridén T. Balance in Single-Limb Stance in Patients with Anterior Cruciate Ligament Injury. Am J Sports Med. 2005;33:1527–37. Lunghi C, Tozzi P, Fusco G. The biomechanical model in manual therapy: Is there an ongoing crisis or just the need to revise the underlying concept and application? J Bodyw Mov Ther. 2016;20:784–99. Warraich Z, Kleim JA. Neural Plasticity: The Biological Substrate For Neurorehabilitation. PM&R. 2010;2. Espí-López GV, López-Martínez S, Inglés M, Serra-Añó P, Aguilar-Rodríguez M. Effect of manual therapy versus proprioceptive neuromuscular facilitation in dynamic balance, mobility and flexibility in field hockey players. A randomized controlled trial. Phys Ther Sport. 2018;32:173–9. Gyer G, Michael J, Inklebarger J, Tedla JS. Spinal manipulation therapy: Is it all about the brain? A current review of the neurophysiological effects of manipulation. J Integr Med. 2019;17:328–37. Espí-López GV, Pavlu D, Arnal-Gómez A, Muñoz-Gómez E, Martinez-Millana A, Marqués-Sulé E. Short-Term Effects of Manual Therapy on Balance: A Multicenter, Randomized, Double-Blind Controlled Trial. J Manipulative Physiol Ther. 2023;46:162–70. Bialosky JE, Beneciuk JM, Bishop MD, Coronado RA, Penza CW, Simon CB, et al. Unraveling the Mechanisms of Manual Therapy: Modeling an Approach. J Orthop Sports Phys Therapy. 2018;48:8–18. Onate JA, Guskiewicz KM, Sullivan RJ. Augmented Feedback Reduces Jump Landing Forces. J Orthop Sports Phys Therapy. 2001;31:511–7. Jung S, Hwang U, Ahn S, Kim J, Kwon O. Effects of Manual Therapy and Mechanical Massage on Spinal Alignment, Extension Range of Motion, Back Extensor Electromyographic Activity, and Thoracic Extension Strength in Individuals with Thoracic Hyperkyphosis: A Randomized Controlled Trial. Evidence-Based Complement Altern Med. 2020;2020:1–10. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Reject after peer review 01 Aug, 2024 Reviewers agreed at journal 30 May, 2024 Reviewers invited by journal 21 May, 2024 Editor assigned by journal 16 May, 2024 First submitted to journal 16 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4365729","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":304945138,"identity":"823c40b6-1719-4a01-9d34-cc6c81d643b4","order_by":0,"name":"Rafał Studnicki","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0002-7074-0472","institution":"Gdanski Uniwersytet Medyczny","correspondingAuthor":true,"prefix":"","firstName":"Rafał","middleName":"","lastName":"Studnicki","suffix":""},{"id":304945139,"identity":"4c40f8af-3956-42a7-9e96-b7a024d4e7e1","order_by":1,"name":"Urszula Tomaszewicz","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Urszula","middleName":"","lastName":"Tomaszewicz","suffix":""},{"id":304945140,"identity":"82e324b1-dffb-43d2-abda-5b980c8f0363","order_by":2,"name":"Rita Hansdorfer-Korzon","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Rita","middleName":"","lastName":"Hansdorfer-Korzon","suffix":""},{"id":304945141,"identity":"eddb4845-c499-404e-b8af-fbd0a67aaeec","order_by":3,"name":"Adam Kawczyński","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Adam","middleName":"","lastName":"Kawczyński","suffix":""}],"badges":[],"createdAt":"2024-05-03 19:32:34","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4365729/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4365729/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":57867336,"identity":"89230db6-0e10-45ff-ab96-d923b6c28af7","added_by":"auto","created_at":"2024-06-06 16:04:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":155195,"visible":true,"origin":"","legend":"\u003cp\u003eParticipants flowchart.\u003c/p\u003e","description":"","filename":"Picture1.png","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/866897dec04ffd6f1086bedd.png"},{"id":57867337,"identity":"89a73b9a-b129-4111-ab9d-987dbc1c2de0","added_by":"auto","created_at":"2024-06-06 16:04:53","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":316367,"visible":true,"origin":"","legend":"\u003cp\u003eDescriptive statistics for within-group and between-group differences in countermovement jump (CMJ) outcomes. DM: diagonal mobilization group; NHC: Nordic hamstring curl; *:significant at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"Picture2.png","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/f09df67bfe80d11d88182762.png"},{"id":57868264,"identity":"1351b952-adad-48f7-9266-7859ed5ea082","added_by":"auto","created_at":"2024-06-06 16:12:53","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":309242,"visible":true,"origin":"","legend":"\u003cp\u003eDescriptive statistics for within-group and between-group differences in squat jump (SJ) outcomes. DM: diagonal mobilization group; NHC: Nordic hamstring curl; Max neg displac: maximum negative displacement; Con: concentric; *:significant at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"Picture3.png","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/893c69f69b026da4aecf5f42.png"},{"id":57867339,"identity":"46126eb1-4c28-4eb2-a025-9e279b9b7ca2","added_by":"auto","created_at":"2024-06-06 16:04:53","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":261156,"visible":true,"origin":"","legend":"\u003cp\u003eDescriptive statistics for within-group and between-group differences in single leg standing test (SLS) outcomes. DM: diagonal mobilization group; NHC: Nordic hamstring curl; CP: center of pressure; Med-Lat: medial-lateral; Anter-post: anterior-posterior; *:significant at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"Picture4.png","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/dd4aff68d5816a55233d384c.png"},{"id":57867340,"identity":"121503b0-2600-497d-a6da-8ffe2cc3f99e","added_by":"auto","created_at":"2024-06-06 16:04:53","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":395944,"visible":true,"origin":"","legend":"\u003cp\u003eDescriptive statistics for within-group and between-group differences in single leg lend and hold test (SLLH) and Lend and hold (LH) test outcomes. DM: diagonal mobilization group; NHC: Nordic hamstring curl; land: landing; stab: stabilization; *:significant at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"Picture5.png","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/48fe0af1c2ad9466a33d5f9f.png"},{"id":57868452,"identity":"8223fd4c-2c20-42fe-bb26-4132c31e59e1","added_by":"auto","created_at":"2024-06-06 16:20:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2132735,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4365729/v1/e20a0003-be92-4c09-802a-7ccdc373e2e6.pdf"}],"financialInterests":"","formattedTitle":"Comparing the acute effects of diagonal mobilization and Nordic hamstring curls on the vertical jump performances, static and dynamic balance, and landing stabilization in youth soccer players: a randomized multi-arm study design","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn soccer, the relationship between muscle force, power, and balance is paramount for player performance and injury prevention [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Enhanced muscle force and power directly correlate with improved sprinting speed, jumping ability, and agility, all essential components of soccer performance [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Studies [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] have consistently demonstrated that stronger and more powerful lower limb muscles enable players to generate greater force during explosive movements such as sprinting, jumping, and tackling, leading to increased acceleration and higher jump heights.\u003c/p\u003e \u003cp\u003eStatic and dynamic balance, meanwhile, are integral aspects of soccer performance and injury risk [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Static balance, characterized by the ability to maintain stability and equilibrium during stationary positions, is crucial to exhibit better control and improving their ability to react quickly to changes in game dynamics [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Dynamic balance, on the other hand, involves the capacity to maintain stability and control while in motion, enabling players to performance complex movements [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Studies have highlighted the importance of dynamic balance in reducing the risk of injury by enhancing neuromuscular coordination and proprioception [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], which are vital for injury prevention mechanisms such as landing stability and joint protection during high-impact activities like sudden direction changes and tackles [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn soccer, where explosive movements like jumping occurs repeatedly, the implementation of suitable warm-up strategies is crucial for injury prevention and optimal performance [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Appropriate warm-up routines enhance neuromuscular activation and proprioception, priming the player\u0026rsquo;s body for the demands of explosive movements as jumping and subsequent landings [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. By incorporating appropriate warm-up strategies, players may improve their ability to cope with landing forces during jumps [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. These exercises may also enhance dynamic and static balance, as well as the time to stabilization after jumps, which are essential components in mitigating injury risk during high-intensity movements.\u003c/p\u003e \u003cp\u003eOne approach to improving immediate strength and preparedness in young soccer players is through diagonal manual mobilization (DM), as suggested by research [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. DM involves manually manipulating joints in the lower limbs, which has been suggested to boost joint flexibility, proprioception, and neuromuscular excitability. These effects may help optimize muscle function for better performance [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Previous reports in healthy adults revealed that manual therapy techniques were effective in improving posture, which can be related to balance enhancement [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Moreover, a single session of joint mobilization significantly improved one leg balance and timed up and go performance in adults compared to placebo [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Also in sports, recent studies on young soccer players have highlighted the positive impact of tissue mobilization on different facets of athletic ability and reducing of injury risk [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite the aforementioned preliminary findings, research on the utilization of DM in sports, particularly in soccer, is scarce. Understanding how DM can enhance acute effects on muscle force and power, as well as static and dynamic balance, holds particular significance. This is especially true in circumstances where specific imbalances or player needs necessitate tailored strategies to mitigate the risk of injury. Furthermore, comparing DM with alternative approaches, such as those centered on specific exercises, is of notable interest. For instance, Nordic curl exercises directly target the hamstring muscles, potentially bolstering eccentric strength and muscle activation [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Studies have shown that performing eccentric exercises like the Nordic curl can heighten muscle activation and prime subsequent muscle contractions [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. While Nordic hamstring curls (NHC) primarily focus on the hamstrings, they also involve other muscles in the posterior chain, including the glutes and lower back. Although they may not directly address balance or landing forces in jumps, they can indirectly contribute to the enhancement of these aspects.\u003c/p\u003e \u003cp\u003eExploring how various strategies, such as DM or NHC, can contribute to enhancing soccer players' performance in terms of muscle force and power, as well as static and dynamic balance, while also reducing landing forces, is of significant interest to practitioners. However, research in this area is lacking, necessitating a deeper analysis to understand the effectiveness of these strategies. Therefore, the aim of this study was to compare the effects of DM, NHC, and a placebo on vertical jump force and power outcomes, as well as static and dynamic balance assessed through unilateral tests. Additionally, the study assessed time to stabilization and force during landing tests conducted among young soccer players. We hypothesize that DM and NHC may yield significantly greater benefits than a placebo on the observed measures.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eThe research methodology adopted a randomized controlled design in which DM and NHC were compared with a placebo group. This design secured against bias by keeping both participants and evaluators unaware of who received the intervention. Prior to the initial assessment, randomization took place to conceal allocation, utilizing a simple randomization method enabled by a research randomizer website. The allocation ratio was 1:1. To ensure blinding process, evaluators remained uninformed about participants' group assignments throughout the study. The intervention protocol consisted of a single session. Participants in the DM group received manual therapy, while those in the placebo group underwent a simulated intervention. In the NHC group, an instructor administered a Nordic exercise intervention.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eEthics\u003c/h2\u003e \u003cp\u003e Approval for the study was granted by the Independent Bioethics Committee for Scientific Research at the Medical University of Gdańsk (approval dated July 7, 2023, Resolution No. NKBBN 392/2023), in conjunction with the AZS Central Academic Sports Center in Gdańsk. Participants were thoroughly briefed on the study's objectives and procedures, with a detailed explanation of the study protocol provided. Written consent was obtained from either the parent or legal guardian before participants' involvement. The study strictly followed the ethical guidelines for human research as outlined in the Declaration of Helsinki.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003ePrior to the commencement of the study, a sample size calculation was performed using G*power software (version 3.1.9.6., Universit\u0026auml;t D\u0026uuml;sseldorf, Germany). The calculation aimed for a statistical power of 0.85 within a two-group ANOVA repeated measures design, accounting for two evaluations, within-between interaction, an effect size of 0.2 (small), and a significance level of 0.05. This analysis yielded a recommended sample size of 72 participants.\u003c/p\u003e \u003cp\u003eParticipants were recruited from the Varsovia Football Academy, a member of the Central Junior League, utilizing convenience sampling. Initially, 76 potential participants were identified and screened for eligibility based on the following criteria: (i) aged between 13 to 15 years old, engaged in regular soccer practice; (ii) absence of lower limb and lumbar spine surgery or injuries within the last 6 months (hip, knee, ankle), no current pain in the hip, knee, or ankle joints, no hypermobility of the lower limb joints, and no history of neurological or connective tissue disorders; and (iii) availability for both assessment time points. Following the exclusion of one participant due to recent injuries within the last month, a total of 75 eligible participants remained for random assignment to study groups (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;FIGURE \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003eTraining intervention\u003c/h2\u003e \u003cdiv id=\"Sec8\" class=\"Section4\"\u003e \u003ch2\u003eDiagonal mobilization\u003c/h2\u003e \u003cp\u003e To provide context, a single intervention session was conducted with participants, following a pre-intervention evaluation and immediately followed by a post-intervention assessment. These interventions occurred on the same day of the week, with a preceding 48-hour rest period to ensure consistency and replicability.\u003c/p\u003e \u003cp\u003eParticipants underwent an active intervention known as DM, involving passive rhythmic gliding mobilization. Before commencement, participants received verbal instructions about the intervention. DM, designed to enhance planned mobility through three-dimensional movements, was administered by a qualified physiotherapist with 25 years of experience in manual therapy. The intervention was consistently performed by the same therapist.\u003c/p\u003e \u003cp\u003eThe procedure began with the participant lying supine, with the upper limbs positioned alongside the torso. The therapist initiated mobilization of the knee joint by gently moving the proximal tibia to enhance internal rotation (medially, cranially, dorsally). In the prone position, mobilization of the hip joint involved gently moving the femoral head (ventrally, medially, cephalad), while mobilization of the sacroiliac joint included gently moving the sacrum to improve nutation (ventrally, cephalad, laterally). Each movement progressed to stage II until tissue tension was palpated, indicating the achievement of tissue tension and subsequent release. The therapist ensured the participant's comfort throughout and conducted mobilization for 2 minutes. This therapeutic protocol was administered once per subject, resulting in a total therapy time of 6 minutes.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003eNordic Hamstring curl\u003c/h2\u003e \u003cp\u003eBefore commencing the study, all participants underwent familiarization with the exercise program. The eccentric hamstring exercise protocol involved executing Nordic hamstring curls against resistance. Participants assumed a kneeling position on the mat and were instructed on proper execution, emphasizing the importance of keeping their arms aligned along their torso to ensure safe landing and maintaining straight backs and hips throughout the movement. Additionally, participants were advised to promptly report any muscle cramps to mitigate the risk of potential strains during exercise. Each volunteer completed three trial runs. The exercise regimen comprised two sets of 8 repetitions each, with a rest interval of 60 seconds between sets. Throughout the entirety of the exercise session, the instructor closely monitored the participants' execution to ensure proper form and technique.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section3\"\u003e \u003ch2\u003ePlacebo\u003c/h2\u003e \u003cp\u003e The placebo intervention followed a comparable procedure: participants received verbal instructions, and the intervention occurred in the same position and timeframe as the active mobilization. To mimic real mobilization, the therapist positioned their hands on the same points of contact, employing minimal movement (1st degree). Both active and placebo interventions had a duration of eight minutes [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eAssessment procedures\u003c/h2\u003e \u003cp\u003eThe assessments occurred 5 minutes before and after the intervention process, all on the same day, within a quiet room maintained at a temperature of 23\u0026ordm;C with a relative humidity of 55%, regulated by an air conditioner. Initially, demographic and anthropometric data were collected from the participants. Following this, participants received a detailed oral explanation of the study procedure. A preliminary attempt at performing the test, without recording results, was permitted.\u003c/p\u003e \u003cp\u003eThe limb chosen for assessment was determined randomly using a \"coin toss\" method. Two members of the research team supervised the tests, paying close attention to changes in torso and pelvic posture during both landing and standing on one leg [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFurthermore, they ensured adherence to the testing sequence and offered verbal encouragement to the volunteers throughout the tests. The collected data were uploaded to a digital platform. The sequence of assessments remained consistent for all participants, commencing with single leg standing (SLS), followed by single leg bend and hold (SLLH), Countermovement Jump Testing (CJT), Squat test (ST), and Jump Testing (JT).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eSingle leg standing (SLS)\u003c/h2\u003e \u003cp\u003eParticipants initiated the evaluation by standing on force plates (ForceDecks, VALD, Brisbane, Australia) in a standard standing posture. With arms by their sides and their gaze fixed forward, participants were instructed to maintain complete stillness for 2\u0026ndash;3 seconds after lifting the other limb. This process was repeated three times, with a 30-second break between each repetition. The resulting data included center of pressure (CP) range in both anterior-posterior (mm) and medial-lateral (mm) directions, as well as mean velocity (mm/s), computed using the VALD ForceDecks software [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The average of the three attempts was used for subsequent data analysis [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eSingle leg lend and hold (SLLH)\u003c/h2\u003e \u003cp\u003eParticipants initiated the evaluation by standing on force plates (ForceDecks, Vald Performance, Brisbane, Australia), positioned 30 cm in front of them. They stood with their feet together, hands on hips, and gaze fixed straight ahead. Each participant was instructed to maintain complete stillness for 2\u0026ndash;3 seconds before each jump. Following this, the instructor directed the participant to execute a single-leg jump and maintain the position until prompted, with the resulting duration recorded (minimum 3 seconds). This sequence was repeated three times, with a 30-second break between each repetition. The collected data included time to stabilization (s) and peak drop landing force (N), which were calculated using the VALD ForceDecks software [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The average of the three attempts was utilized for subsequent data analysis [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eCountermovement Jump Testing (CJT)\u003c/h2\u003e \u003cp\u003eThe participant began from a standard standing position on the research platform, with hands on hips and gaze fixed straight ahead. They were instructed to maintain complete stillness for 2\u0026ndash;3 seconds both before and between each jump. The instructor then directed the participant to execute a two-legged jump, aiming to achieve maximum height. This process was repeated three times.\u003c/p\u003e \u003cp\u003eOutcome variables obtained included jump height, peak power and peak landing force, computed using the VALD ForceDecks software. The final mean strength variables utilized for analysis were the average values derived from the three jumps performed [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eSquat test (ST)\u003c/h2\u003e \u003cp\u003eParticipants performed an unloaded squat with maximum range of motion on ForceDecks force plates (Vald Performance, Brisbane, Australia), while maintaining a straight torso position. Although participants were instructed to adopt their usual comfortable foot position, the width between their feet was measured to ensure consistent positioning for subsequent examinations. Athletes were instructed to complete three repetitions, with a 30-second rest interval between each repetition.\u003c/p\u003e \u003cp\u003eThe results obtained from each trial included peak force (N), maximum negative displacement (cm), and concentric peak power per body mass (W/kg). The trial producing the average maximum force, as calculated by the VALD ForceDecks software, was selected for statistical analysis.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eLend and hold (LH)\u003c/h2\u003e \u003cp\u003eThe participant began the study by standing on ForceDecks force plates (VALD, Brisbane, Australia) in a normal standing position. The participant stood with arms alongside the torso and gaze fixed straight ahead. The participant was instructed to remain completely still for 2\u0026ndash;3 seconds before and between each jump. The instructor then directed the participant to perform a two-legged jump to jump as high as possible. This procedure was repeated three times. The resulting data included Time to Stabilization (s) and Peak Drop Landing Force (N), calculated by the VALD ForceDecks software. The final variables for mean force used for analysis were the calculated average values from the three jumps performed.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eStatistical procedures\u003c/h2\u003e \u003cp\u003eAfter investigating potential outliers, descriptive statistics were presented, utilizing means and standard deviations. Before proceeding to inferential statistics, the normality of the sample underwent evaluation, and it was confirmed through the Kolmogorov-Smirnov test (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Similarly, the assumption of homogeneity was validated via Levene\u0026rsquo;s test (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Given the study's design (two assessments for three groups), a mixed ANOVA was utilized to examine interactions between time and groups. This analysis also involved the calculation of partial eta squared (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e). Furthermore, post-hoc comparisons were conducted using the Bonferroni test. All statistical analyses were carried out using JASP software (version 0.18.3, University of Amsterdam, The Netherlands), with a predetermined significance level of p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eSeventy-five young male soccer players, averaging 13.9 years of age (\u0026plusmn;\u0026thinsp;0.9), participated in this study. On average, they stood at 174.4 cm tall (\u0026plusmn;\u0026thinsp;8.1) and weighed 60.6 kg (\u0026plusmn;\u0026thinsp;8.9). These participants are affiliated with a regional-level soccer club, engaging in three training sessions per week in addition to matches. After random allocation to each group, the following are the main characteristics for each group: DM (N\u0026thinsp;=\u0026thinsp;25; mean age 13.7 years\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8; height 170.9 cm\u0026thinsp;\u0026plusmn;\u0026thinsp;8.5; weight 55.5 kg\u0026thinsp;\u0026plusmn;\u0026thinsp;6.5); NHC (N\u0026thinsp;=\u0026thinsp;25, mean age 14.2 years\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9; height 175.6 cm\u0026thinsp;\u0026plusmn;\u0026thinsp;7.1; weight 64.0 kg\u0026thinsp;\u0026plusmn;\u0026thinsp;9.1); and placebo (N\u0026thinsp;=\u0026thinsp;25; mean age 13.9 years\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9; height 174.4 cm\u0026thinsp;\u0026plusmn;\u0026thinsp;8.1; weight 60.6 kg\u0026thinsp;\u0026plusmn;\u0026thinsp;8.9).\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the descriptive statistics of the outcomes associated with CMJ and SJ performance before and after the interventions. Significant interactions time \u0026times; group were found in CMJ height (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=4.800; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.011; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e\u0026lt;0.118), CMJ peak landing force (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=5.351; \u003cem\u003ep\u003c/em\u003e=0.007; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.129), CMJ peak power (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.362; \u003cem\u003ep\u003c/em\u003e=0.101; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.062), and SJ concentric peak power (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.540; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.034; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.090).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescriptive statistics (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation) of the outcomes associated with CMJ and SJ performance before and after the interventions.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDM (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNHC (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePlacebo (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBetween-group analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCMJ height (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e18.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e18.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e18.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=0.005; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.995; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e21.0\u0026thinsp;\u0026plusmn;\u0026thinsp;6.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e17.8\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e17.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.624; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.032*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.091\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCMJ peak landing force (N)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1588.7\u0026thinsp;\u0026plusmn;\u0026thinsp;582.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1691.3\u0026thinsp;\u0026plusmn;\u0026thinsp;661.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1681.4\u0026thinsp;\u0026plusmn;\u0026thinsp;509.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=0.232; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.794; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.006\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1414.8\u0026thinsp;\u0026plusmn;\u0026thinsp;584.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1687.1\u0026thinsp;\u0026plusmn;\u0026thinsp;554.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2047.3\u0026thinsp;\u0026plusmn;\u0026thinsp;611.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=7.385; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.170\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCMJ peak power (W/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e36.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e35.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e35.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=0.129; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.879; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.004\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.1\u0026thinsp;\u0026plusmn;\u0026thinsp;6.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e35.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e34.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.217; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.116; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.058\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSJ peak force (N)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e486.5\u0026thinsp;\u0026plusmn;\u0026thinsp;118.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e533.5\u0026thinsp;\u0026plusmn;\u0026thinsp;114.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e557.2\u0026thinsp;\u0026plusmn;\u0026thinsp;120.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.323; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.105; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.061\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e534.9\u0026thinsp;\u0026plusmn;\u0026thinsp;144.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e560.4\u0026thinsp;\u0026plusmn;\u0026thinsp;144.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e521.4\u0026thinsp;\u0026plusmn;\u0026thinsp;156.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=0.442; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.645; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.012\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSJ maximum negative displacement (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;36.5\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;35.3\u0026thinsp;\u0026plusmn;\u0026thinsp;7.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;33.3\u0026thinsp;\u0026plusmn;\u0026thinsp;7.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.252; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.292; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.034\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;37.1\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;34.2\u0026thinsp;\u0026plusmn;\u0026thinsp;8.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;37.4\u0026thinsp;\u0026plusmn;\u0026thinsp;8.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.372; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.260; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.037\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSJ concentric peak power (W/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e8.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e7.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e8.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.500; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.230; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.040\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e8.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e6.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=7.730; \u003cem\u003ep\u0026thinsp;\u0026lt;\u003c/em\u003e\u0026thinsp;0.001*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.177\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eDM: diagonal mobilization group; NHC: Nordic hamstring curl; CMJ: countermovement jump; SJ: squat jump; *: significantly different at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the descriptive statistics of the outcomes associated with SLS, SLLH and LH performance before and after the interventions. SLS CP range anterior-posterior (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=4.805; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.011; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.118), SLLH time to stabilization (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=15.391; \u003cem\u003ep\u003c/em\u003e\u0026lt;0.001; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.299), SLLH peak drop landing force (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=8.237; \u003cem\u003ep\u003c/em\u003e\u0026lt;0.001; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.186), LH time to stabilization (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.608; \u003cem\u003ep\u003c/em\u003e=0.032; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.041) and LH peak drop landing force (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=4.711; \u003cem\u003ep\u003c/em\u003e=0.012; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.116). However, no significant interactions were found in SJ peak force (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.317; \u003cem\u003ep\u003c/em\u003e=0.106; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.060), SJ maximum negative displacement (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.230; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.115; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.058), SLS CP range media-lateral (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.760; \u003cem\u003ep\u003c/em\u003e=0.179; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.047), and SLS mean velocity (\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=0.163; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.850; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.005).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescriptive statistics (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation) of the outcomes associated with CMJ and SJ performance before and after the interventions.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDM (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNHC (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePlacebo (n\u0026thinsp;=\u0026thinsp;25)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBetween-group analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSLS CP range media-lateral (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e30.4\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e28.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e32.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.667; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.076; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.069\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e29.6\u0026thinsp;\u0026plusmn;\u0026thinsp;6.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e29.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e34.4\u0026thinsp;\u0026plusmn;\u0026thinsp;6.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=4.738; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.012*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.116\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSLS CP range anterior-posterior (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e48.0\u0026thinsp;\u0026plusmn;\u0026thinsp;21.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e47.4\u0026thinsp;\u0026plusmn;\u0026thinsp;17.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e56.6\u0026thinsp;\u0026plusmn;\u0026thinsp;19.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.760; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.179; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.047\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e49.2\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e48.7\u0026thinsp;\u0026plusmn;\u0026thinsp;17.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e64.2\u0026thinsp;\u0026plusmn;\u0026thinsp;19.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=7.053; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.164\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSLS mean velocity (mm/s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e55.8\u0026thinsp;\u0026plusmn;\u0026thinsp;17.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e55.5\u0026thinsp;\u0026plusmn;\u0026thinsp;18.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e62.8\u0026thinsp;\u0026plusmn;\u0026thinsp;19.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.303; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.278; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.035\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e50.8\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e55.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e48.1\u0026thinsp;\u0026plusmn;\u0026thinsp;16.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.424; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.247; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.038\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSLLH time to stabilization (s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.54\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=2.996; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.056; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.077\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.37\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.42\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.970; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.023*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.099\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSLLH peak drop landing force (N)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e827.2\u0026thinsp;\u0026plusmn;\u0026thinsp;189.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e824.3\u0026thinsp;\u0026plusmn;\u0026thinsp;153.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e937.2\u0026thinsp;\u0026plusmn;\u0026thinsp;198.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.129; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.050; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.080\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e856.9\u0026thinsp;\u0026plusmn;\u0026thinsp;317.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e863.7\u0026thinsp;\u0026plusmn;\u0026thinsp;246.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1168.2\u0026thinsp;\u0026plusmn;\u0026thinsp;314.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=9.100; \u003cem\u003ep\u0026thinsp;\u0026lt;\u003c/em\u003e\u0026thinsp;0.001*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.202\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLH time to stabilization (s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=1.551; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.219; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.041\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.53\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.491; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.036*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.088\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLH peak drop landing force (N)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1278.1\u0026thinsp;\u0026plusmn;\u0026thinsp;584.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1534.8\u0026thinsp;\u0026plusmn;\u0026thinsp;367.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1660.2\u0026thinsp;\u0026plusmn;\u0026thinsp;488.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=3.979; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.023; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.100\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1081.6\u0026thinsp;\u0026plusmn;\u0026thinsp;345.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1469.5\u0026thinsp;\u0026plusmn;\u0026thinsp;602.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1915.0\u0026thinsp;\u0026plusmn;\u0026thinsp;590.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003csub\u003e2,72\u003c/sub\u003e=15.685; \u003cem\u003ep\u0026thinsp;\u0026lt;\u003c/em\u003e\u0026thinsp;0.001*; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.303\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eDM: diagonal mobilization group; NHC: Nordic hamstring curl; SLS: single leg standing test; SLLH: single leg lend and hold test; LH: Lend and hold test; CP: center of pressure; *: significantly different at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows both between-group and within-group descriptive statistics regarding the outcomes of the CMJ test. The between-group analysis showed that the placebo group exhibited significantly greater CMJ landing force compared to the DM group in the post-intervention phase (632.5 N; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Within-group analysis revealed that the DM group experienced a significant improvement in CMJ height (2.4 cm; p\u0026thinsp;=\u0026thinsp;0.007), whereas the placebo group demonstrated a significant increase in CMJ landing force (365.9 N; p\u0026thinsp;=\u0026thinsp;0.003) following the intervention.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;FIGURE \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows both between-group and within-group descriptive statistics regarding the outcomes of the SJ test. The between-group analysis showed that the placebo group exhibited significantly smaller SJ concentric peak power compared to the DM group in the post-intervention phase (2.3 W/kg; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Within-group analysis revealed that the DM group experienced a significant increase in SJ concentric peak power (1.2 W/kg; p\u0026thinsp;=\u0026thinsp;0.006), whereas the placebo group demonstrated a significant increase in SJ maximum negative displacement (4.1 cm; p\u0026thinsp;=\u0026thinsp;0.024) and decrease in SJ concentric peak power (1.1 W/kg; p\u0026thinsp;=\u0026thinsp;0.0013) following the intervention. The NHC group significantly increased SJ concentric peak power after the intervention (0.9 W/kg; p\u0026thinsp;=\u0026thinsp;0.045).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec22\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;FIGURE \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows both between-group and within-group descriptive statistics regarding the outcomes of the SLS test. The between-group analysis showed that the placebo group exhibited significantly greater CP medial-lateral (4.8 mm; p\u0026thinsp;=\u0026thinsp;0.023) and CP anterior-posterior (15.0 mm; p\u0026thinsp;=\u0026thinsp;0.006) compared to the DM group in the post-intervention phase. Also, placebo presented significantly greater CP medial-lateral (4.5 mm; p\u0026thinsp;=\u0026thinsp;0.036) and CP anterior-posterior (15.5 mm; p\u0026thinsp;=\u0026thinsp;0.004) compared to the NHC group. Within-group analysis revealed that the placebo group experienced a significant increase in CP anterior-posterior (7.6 mm; p\u0026thinsp;=\u0026thinsp;0.030), whereas the demonstrated a significant decrease in mean velocity (14.7 mm/s; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;FIGURE \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows both between-group and within-group descriptive statistics regarding the outcomes of the SLLH and LH tests. The between-group analysis showed that the placebo group exhibited significantly greater SLLH time to stabilization (0.12s; p\u0026thinsp;=\u0026thinsp;0.019) and SLLH peak landing force (311.3N; p\u0026thinsp;=\u0026thinsp;0.001) and LH peak landing force (833.4 N; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) compared to the DM group in the post-intervention phase. Moreover, placebo also presented significantly greater SLLH peak landing force compared to NHC group (304.5 N; p\u0026thinsp;=\u0026thinsp;0.001). Considering the LH peak landing force, NHC had significantly greater values than DM (445.5 N; p\u0026thinsp;=\u0026thinsp;0.033).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWithin-group analysis revealed that the DM group experienced a significant decrease in SLLH time to stabilization (0.17 s; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and LH time to stabilization (0.08 s; p\u0026thinsp;=\u0026thinsp;0.034) after the intervention. On the other hand, placebo group experienced a significantly increase in SLLH peak landing force (231.0 N; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and LH peak landing force (254.8 N; p\u0026thinsp;=\u0026thinsp;0.020).\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec24\" class=\"Section2\"\u003e \u003ch2\u003e\u0026lt;\u0026lt;\u0026lt;FIGURE \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e\u0026gt;\u0026gt;\u0026gt;\u003c/h2\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study revealed that the DM group exhibited significant improvements in several key outcomes compared to the placebo group. Specifically, participants in the DM group showed enhancements in CMJ landing force, SJ concentric peak power, balance in both anterior-posterior and medial-lateral center of pressure, time to stabilization in the SLLH test, and peak landing force in both SLLH and LH tests. When comparing the DM group to the NHC group, no significant differences were observed across most variables. However, it is worth noting that the DM group displayed significantly better results than the NHC group in terms of LH peak landing force.\u003c/p\u003e \u003cp\u003eManual therapy focused on DM significantly enhanced static balance in the anterior-posterior and medial-lateral center of pressure during the SLS test, possibly being justified be some underlying mechanisms. DM techniques targeted specific muscle groups and joint structures in lower limbs, possibly promoting proprioceptive feedback and neuromuscular control [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. By applying manual forces diagonally across the region, these techniques may engage sensory receptors within muscles, tendons, and ligaments, eliciting proprioceptive signals that enhance the brain's awareness of limb position and movement [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. This heightened proprioception allows for more precise adjustments in muscle activation and joint positioning, crucial for maintaining balance during single-leg stance [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Furthermore, DM can modulate neural pathways involved in postural control [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Research suggests that manual therapy techniques, including mobilization, can influence the excitability of neural circuits within the central nervous system, particularly those related to balance and coordination [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur results also found that DM significantly improved the time to stabilization in the SLLH and LH tests, possibly also justified by eliciting proprioceptive feedback that enhances neuromuscular control and coordination. For example, a study by Esp\u0026iacute;-L\u0026oacute;pez et al [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e] found that manual therapy techniques, including mobilization, led to increased dynamic balance possibly due enhancing proprioceptive ability. Also, research has shown that manual therapy techniques can influence cortical excitability and spinal reflex arcs, leading to enhanced motor output and coordination [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. For instance, a study by Lehr et al [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] revealed that mobilization with movement significantly enhanced dynamic balance in health individuals.\u003c/p\u003e \u003cp\u003eBy possibly improving proprioceptive input, diagonal mobilization facilitates more precise adjustments in muscle activation and joint positioning, which are essential for stabilizing the body during dynamic tasks like the SLLH and LH tests. Additionally, manual therapy interventions can modulate neural pathways involved in motor control and balance [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur results also revealed that DM significantly improve landing force in the SLLH and LH tests, and CMJ. Although similar studies investigating this phenomenon have not been observed, a previous study revealed that high-impact landing forces were reduced through the implementation of augmented feedback information instructing individuals on proper landing techniques [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. In our case, DM may have acted as a regulator of proprioception, facilitating improved coordination of muscle activity, thereby reducing excessive landing forces and promoting smoother force absorption. Additionally, by targeting joint restrictions and asymmetries, manual therapy techniques optimize the alignment of the kinetic chain, thereby reducing the risk of excessive loading and injury during landing tasks. Research has shown that manual therapy interventions can improve joint range of motion and biomechanical alignment. For example, a study by Stanek et al [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e] found that manual therapy techniques improved tibial range of motion. These biomechanical improvements can enhance the ability to absorb and distribute forces during landing, resulting in reduced landing forces and improved landing mechanics.\u003c/p\u003e \u003cp\u003eWhile our study revealed promising results regarding the effectiveness of DM in improving various outcomes related to balance, neuromuscular control, and landing force, several limitations should be acknowledged. Firstly, our sample size was exclusively related with youth players, limiting the generalizability of our findings to elite populations. Future research should aim to test these findings with elite players aiming to ensure the robustness of the observed effects. Furthermore, despite our efforts to introduce a gentle approach in the control group to mimic a placebo effect, it may not effectively evoke the placebo response. This limitation is noteworthy, particularly in manual therapy, where the identification and implementation of placebos are not as straightforward as in other clinical trials. Additionally, the lack of a long-term follow-up assessment in our study prevents us from understanding the durability of the improvements seen with DM over time. Longitudinal studies are warranted to evaluate the sustained effects of DM interventions beyond the immediate post-treatment period. Furthermore, the mechanisms underlying the observed improvements with DM remain speculative and warrant further investigation. Incorporating neurophysiological assessments, such as electromyography or functional MRI, could elucidate the neurobiological mechanisms through which DM influences balance and neuromuscular control. Additionally, exploring the optimal dosage and frequency of DM interventions could help optimize treatment protocols for maximal effectiveness. Despite these limitations, our study provides valuable insights into the potential benefits of DM in improving balance and neuromuscular function, laying the groundwork for future research to address these gaps and refine our understanding of its therapeutic mechanisms and clinical applications.\u003c/p\u003e \u003cp\u003eFrom a clinical perspective, our findings indicate that DM can be integrated by practitioners to augment several performance parameters in young soccer players. These include enhanced landing force in CMJ, increased concentric peak power in SJ, and improvements in balance metrics such as anterior-posterior and medial-lateral center of pressure. Notably, DM should be applied cautiously, tailored to individual player needs to address specific imbalances. Furthermore, in the context of return-to-play scenarios, the incorporation of DM may offer additional benefits, potentially mitigating injury risks before training sessions or matches.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe study findings revealed the significant benefits of DM in improving various key outcomes compared to a placebo group, particularly evident in enhancements in CMJ landing force, SJ concentric peak power, and balance metrics such as anterior-posterior and medial-lateral center of pressure. Additionally, DM resulted in significant improvements in time to stabilization during specific tests, indicating enhanced neuromuscular control. Despite these promising results, the study acknowledges limitations related to the sample selected (youth players) and the lack of information about the longitudinal extension of the effects, underscoring the need for future research to validate findings across diverse populations and investigate underlying mechanisms through neurophysiological assessments. Nonetheless, this study suggests that DM can be particularly beneficial for athletes requiring individualized therapeutic interventions prior to training or matches, especially for improving balance and movement control, thereby potentially mitigating injury risk factors.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics Approval and Consent to participate.\u003c/p\u003e\n\u003cp\u003eApproval for the study was granted by the Independent Bioethics Committee for Scientific Research at the Medical University of Gdańsk (approval dated July 7, 2023, Resolution No. NKBBN 392/2023), in conjunction with the AZS Central Academic Sports Center in Gdańsk. Participants were thoroughly briefed on the study\u0026apos;s objectives and procedures, with a detailed explanation of the study protocol provided. Written consent was obtained from either the parent or legal guardian before participants\u0026apos; involvement. The study strictly followed the ethical guidelines for human research as outlined in the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003eAcknowledgments\u003c/p\u003e\n\u003cp\u003eThe authors have no acknowledgments.\u003c/p\u003e\n\u003cp\u003eAuthor contributions\u003c/p\u003e\n\u003cp\u003eRS \u0026ndash; conception, performance of work, interpretation or analysis of data, preparation of the manuscript, revision for important intellectual content.\u003c/p\u003e\n\u003cp\u003eUT \u0026ndash; performance of work, preparation of the manuscript, revision for important intellectual content\u003c/p\u003e\n\u003cp\u003eRHK \u0026ndash; performance of work, preparation of the manuscript, revision for important intellectual content\u003c/p\u003e\n\u003cp\u003eAK \u0026ndash; performance of work, preparation of the manuscript, revision for important intellectual content\u003c/p\u003e\n\u003cp\u003eCompeting Interest\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003eConsent for publication.\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003eAvailability of Data and Material\u003c/p\u003e\n\u003cp\u003eThe data is secured and only co-authors have access to it. Data are available from the corresponding author upon request\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThe authors report no funding\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eErgen E, Ulkar B. Proprioception and Ankle Injuries in Soccer. Clin Sports Med. 2008;27:195\u0026ndash;217.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePe\u0026ntilde;ailillo L, Esp\u0026iacute;ldora F, Jannas-Vela S, Mujika I, Zbinden-Foncea H. Muscle Strength and Speed Performance in Youth Soccer Players. J Hum Kinet. 2016;50:203\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSuchomel TJ, Nimphius S, Stone MH. The Importance of Muscular Strength in Athletic Performance. Sports Med. 2016;46:1419\u0026ndash;49.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDunsky A, Barzilay I, Fox O. 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Short-Term Effects of Manual Therapy on Balance: A Multicenter, Randomized, Double-Blind Controlled Trial. J Manipulative Physiol Ther. 2023;46:162\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBialosky JE, Beneciuk JM, Bishop MD, Coronado RA, Penza CW, Simon CB, et al. Unraveling the Mechanisms of Manual Therapy: Modeling an Approach. J Orthop Sports Phys Therapy. 2018;48:8\u0026ndash;18.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOnate JA, Guskiewicz KM, Sullivan RJ. Augmented Feedback Reduces Jump Landing Forces. J Orthop Sports Phys Therapy. 2001;31:511\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJung S, Hwang U, Ahn S, Kim J, Kwon O. Effects of Manual Therapy and Mechanical Massage on Spinal Alignment, Extension Range of Motion, Back Extensor Electromyographic Activity, and Thoracic Extension Strength in Individuals with Thoracic Hyperkyphosis: A Randomized Controlled Trial. Evidence-Based Complement Altern Med. 2020;2020:1\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"chiropractic-and-manual-therapies","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chmt","sideBox":"Learn more about [Chiropractic \u0026 Manual Therapies](http://chiromt.biomedcentral.com/)","snPcode":"12998","submissionUrl":"https://submission.springernature.com/new-submission/12998/3","title":"Chiropractic \u0026 Manual Therapies","twitterHandle":"@ChiroManTher","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"football, musculoskeletal manipulations, postural balance, biomechanics","lastPublishedDoi":"10.21203/rs.3.rs-4365729/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4365729/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eEnsuring the utilization of appropriate techniques that maximize soccer performance in terms of force, muscular power, balance, and stabilization is crucial for mitigating injury risk. Aim: The objective of this study was to compare the effects of diagonal mobilization (DM), Nordic hamstring curls (NHC), and placebo on vertical jump force and power outcomes, as well as static and dynamic balance assessed through unilateral tests, along with time to stabilization and force during landing tests conducted among young soccer players. Methods: A randomized multi-arm study design was employed. Seventy-five young male soccer players participated in this study, with an average age of 13.9 years (\u0026plusmn;\u0026thinsp;0.9), height of 174.4 cm (\u0026plusmn;\u0026thinsp;8.1), and weight of 60.6 kg (\u0026plusmn;\u0026thinsp;8.9). Participants were randomly assigned to one of three groups and were assessed both before and after the intervention. The assessment included tests such as the countermovement jump (CMJ), squat jump (SJ), single-leg standing (SLS), single-leg hold (SLLH), and the land and hold test (LH), all conducted on a force platform. Results: Significant interactions time \u0026times; group were found in CMJ height (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.011; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e\u0026lt;0.118), CMJ peak landing force (\u003cem\u003ep\u003c/em\u003e=0.007; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.129), CMJ peak power (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.101; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.062), and SJ concentric peak power (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.034; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.090). Moreover, SLS CP range anterior-posterior (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.011; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.118), SLLH time to stabilization (\u003cem\u003ep\u003c/em\u003e\u0026lt;0.001; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.299), SLLH peak drop landing force (\u003cem\u003ep\u003c/em\u003e\u0026lt;0.001; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.186), LH time to stabilization (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.032; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.041) and LH peak drop landing force (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.012; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\eta }_{p}^{2}\\)\u003c/span\u003e\u003c/span\u003e=0.116). The between-group analysis showed that the placebo group exhibited significantly greater CMJ landing force compared to the DM group in the post-intervention phase (p\u0026lt;0.001). Additionally, the placebo group exhibited significantly smaller SJ concentric peak power compared to the DM group in the post-intervention phase (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The placebo group exhibited significantly greater CP medial-lateral (p=0.023) and CP anterior-posterior (p=0.006) compared to the DM group in the post-intervention phase. Also, placebo presented significantly greater CP medial-lateral (p=0.036) and CP anterior-posterior (p\u0026thinsp;=\u0026thinsp;0.004) compared to the NHC group. Conclusions: In conclusion, DM revealed significant effectiveness in enhancing landing forces during both CMJ and SJ, while also improving static and dynamic balance parameters compared to the placebo. Although it did not show significant superiority to NHC in most parameters, DM exhibited significant superiority over NHC during the LH. DM appears to be a promising and effective approach for enhancing performance and minimizing injury risk parameters in soccer players.\u003c/p\u003e","manuscriptTitle":"Comparing the acute effects of diagonal mobilization and Nordic hamstring curls on the vertical jump performances, static and dynamic balance, and landing stabilization in youth soccer players: a randomized multi-arm study design","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-06 16:04:49","doi":"10.21203/rs.3.rs-4365729/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Reject after peer review","date":"2024-08-01T22:15:27+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-05-31T02:41:35+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-21T09:40:07+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-17T00:36:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Chiropractic \u0026 Manual Therapies","date":"2024-05-16T04:52:15+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"chiropractic-and-manual-therapies","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chmt","sideBox":"Learn more about [Chiropractic \u0026 Manual Therapies](http://chiromt.biomedcentral.com/)","snPcode":"12998","submissionUrl":"https://submission.springernature.com/new-submission/12998/3","title":"Chiropractic \u0026 Manual Therapies","twitterHandle":"@ChiroManTher","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d3124013-d85e-4547-b110-00f3c5407acc","owner":[],"postedDate":"June 6th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-06-06T16:04:49+00:00","versionOfRecord":[],"versionCreatedAt":"2024-06-06 16:04:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4365729","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4365729","identity":"rs-4365729","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}