A study of the effects of vibration training at different frequencies on lower limb muscle strength in semi-elite short track speed skaters

A study of the effects of vibration training at different frequencies on lower limb muscle strength in semi-elite short track speed skaters | 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 A study of the effects of vibration training at different frequencies on lower limb muscle strength in semi-elite short track speed skaters Qianrong Qi, Yuanyuan Gao This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5484550/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The aim of this study is to examine the impact of lower limb muscle strength in semi-elite athletes engaged in short track speed skating through the lens of different frequency vibration training. The methodology employed in this study is as follows: The study employs an experimental methodology. Subsequent to the screening process, a total of 75 male semi-elite short track speed skaters were selected from the Shenyang Institute of Physical Education. The participants were randomly assigned to one of three groups: a 30 Hz frequency vibration group comprising 25 individuals, a 50 Hz frequency vibration group comprising 25 individuals, and a control group comprising 25 individuals. The experimental group underwent the intervention on two occasions per week, with three groups participating on each occasion. The total duration of the intervention was four weeks, with an amplitude of 2mm. Each session comprised 30 seconds of whole-body vibration training. The control group comprised 25 individuals who performed the same duration and posture of semi-squatting movement on the vibration platform, but without additional vibration stimulation. The maximum strength, rapid strength, and strength endurance of the knee flexors and extensors during centripetal contraction were evaluated both before and after the intervention. The results are presented in the following manner: (1) Maximum power: the peak moments of the knee flexor and extensor muscle groups of both legs of the subjects exhibited a notable enhancement in comparison to the values observed prior to the training period (P < 0.01). The vibration frequency of 50 Hz demonstrated a more pronounced impact on the improvement of the peak moments of the knee flexor muscle groups on both sides. (2) Rapid power: the 50Hz vibration frequency was observed to have a more significant enhancement effect on the peak power of the bilateral knee flexor muscle groups and the left knee extensor muscle groups (P < 0.05). (3) Muscular endurance: a significant difference was observed in the total work of the subjects' bilateral knee flexor and extensor muscle groups with different frequencies of vibration stimulation (P < 0.05), with a highly significant difference noted in the total work of the left knee flexor muscle group (P < 0.01). It can be concluded that four weeks of vibration training at different frequencies can significantly improve the muscle strength of the knee joints in semi-elite short track speed skaters. Furthermore, the results demonstrate that a vibration frequency of 50 Hz is more effective than 30 Hz in terms of maximal and rapid strength when the amplitude is 2 mm. vibration training different frequencies short track speed skating lower limb muscle strength Figures Figure 1 Figure 2 Figure 3 Introduction Short-distance speed skating, also known as short track speed skating, is a sport that requires a high level of physical dominance, particularly within the class of speed-related activities. The competitive abilities of athletes in this field are significantly influenced by their physical fitness, technical abilities, and strategic proficiency. To excel in this sport, athletes must possess a rapid nerve impulse conduction speed, superior quality of strength, and the ability to adapt to the rapid movements and frequent changes in direction on the ice. Therefore, a strong foundation of lower limb muscle strength is essential for short-track speed skating athletes to achieve optimal performance [1] . Muscle strength can be defined as the body's capacity to counteract resistance. The mechanical properties of muscle are primarily related to four key factors: the initial length of the muscle, the physiological cross-sectional area of the muscle, external stimuli, and the level of central activation.Whole body vibration training (WBVT) is a method of exercise that involves the human body in a specific position on a vibration platform. The vibration frequency, amplitude, time and other parameters can be adjusted to stimulate the muscles mechanically, thereby promoting the nervous system's ability to regulate and enhance the human body's motor functions. This type of training has been demonstrated to enhance muscle strength [2] ,explosive strength [3] and balance in a relatively short period of time. Additionally, it has been shown to improve neurocognitive abilities by providing the athlete with an unstable environment [4] , which is then utilised to stimulate the proprioceptors, including the muscle and tendon plexus [5] .At present, the frequency of whole body vibration training is predominantly concentrated within the 20-50 Hz range, with the majority of training programmes lasting between four and eight weeks [6] .The primary objective is to enhance the maximum strength and explosive power of muscles, while also capitalising on the elastic potential energy of muscles. The efficacy of different frequencies in muscle strength training has been the subject of considerable research. While studies have demonstrated the effectiveness of a range of frequencies, including both medium and high frequencies and low frequencies, the optimal frequency for developing strength remains a topic of ongoing investigation [7, 8] . In this experiment, the vibration frequencies of medium-low (30 Hz) and medium-high (50 Hz) were used to conduct a four-week [9] training intervention under the condition of 2 mm amplitude. The aim was to compare the changes in lower limb muscle strength before and after the training in order to investigate the effects of whole-body vibration training on semi-elite athletes of short-track speed skating.It is anticipated that whole-body vibration training will provide a theoretical foundation for exercise training in short-track speed skating, while elucidating the optimal setting parameters to augment muscle strength. 1 Objects of study and methodology 1.1 research target Prior to the commencement of the experiment, a total of 80 short-track speed skating semi-elite athletes were recruited. Following the screening process, 75 male short-track speed skating semi-elite athletes [10] from the Shenyang Sports Institute were selected as the experimental subjects (Table 1). Subsequently, a one-way ANOVA analysis was conducted on the subjects' basic information and pre-test results. The obtained indexes demonstrated no significant difference between the groups. Subsequently, a random grouping was conducted using the random number generator in SPSS (the fixed value was 20231010), resulting in the formation of three groups: a vibration frequency of 30Hz group comprising 25 individuals, a 50Hz group comprising 25 individuals, and a control group comprising 25 individuals. Inclusion criteria: subjects were required to be healthy, without a history of cardiovascular or cerebrovascular disease, and free from any recent muscle or joint injuries. Additionally, they were not permitted to have undergone any surgical procedures within the previous six months and were required to refrain from engaging in strenuous exercise for a minimum of 24 hours prior to the test. Furthermore, they were asked to abstain from consuming beverages containing caffeine, creatine, alcohol, and other stimulants, and were prohibited from taking any anabolic drugs, including protein powder, with the intention of increasing muscle strength. The study was approved by the Ethics Committee of the Shenyang Sport University. All subjects were novices in vibration training and provided informed consent prior to participation. Table 1 Subjects' basic information（M±SD） 30 Hz group (n=25) Group 50Hz (n=25) Control group (n=25) F P Age/years 23.80±2.16 23.64±2.16 23.88±1.69 0.092 0.912 Height/cm 1.79±0.05 1.81±0.05 1.81±0.04 0.860 0.428 Weight/kg 79.68±7.85 83.12±7.99 82.43±9.77 1.122 0.331 (Note: P<0.05 indicates a significant difference between the pre-intervention groups, and P<0.01 indicates a highly significant difference between the pre-intervention groups, same below.) 1.2 Research methodology 1.2.1 Experimental programme The experimental period commenced on 30 October 2023 and concluded on 25 December 2023. During the aforementioned period, the subjects were introduced to the vibration training apparatus and isokinetic muscle testing system between the dates of 30 October and 3 November. Between the dates of 6 November and 12 November, the subjects underwent a de-warming process. The pre-experimental testing phase commenced on 13 November and concluded on 17 November. The vibration training intervention phase commenced on 21 November and concluded on 14 December. The post-experimental testing phase commenced on 18 December and concluded on 25 December, marking the conclusion of the experiment. The experiment was conducted at a fitness centre located on the ground floor of Feibing Hall, which is part of the Shenyang Institute of Physical Education. The test location is the isokinetic muscle strength test, which is conducted in the Science and Technology Building.The apparatus and equipment used in the experiment are as follows: The apparatus employed was a Power Plate Pro5 vibration trainer, in conjunction with an IsoMed 2000 isokinetic muscle strength testing system. Prior to the commencement of this study, the athletes underwent a training period of one week. This included familiarisation with the vibration training equipment, the movements to be performed, and pre-experimental testing of lower limb muscle strength. It has been demonstrated that the development of a whole-body vibration training programme must consider the impact of gender. Consequently, this experiment was conducted with male subjects [11] .The requirements for whole-body vibration training action posture are as follows: the subject's torso should be naturally leaning forward, with the hips and knees flexed to a semi-squatting position on the vibration platform (knee angle of approximately 120°). In order to maintain the subject's head posture, the focus should be on the sign in front of the mark point, with the hands holding the handrail in vain, the two feet wider than the shoulder, the whole foot on the ground with the toes slightly outwardly spread. Each training session comprises three groups, with each group undergoing the training three times. The vibration frequency is 30Hz for the first group of 10 people and 50Hz for the second group of 10 people. Each vibration time is 30 seconds. The control group of 10 people performs the same length and posture of the semi-squatting action on the vibration platform, but without additional vibration stimulation. The three groups of subjects undergo sub-intervals of 1-3 minutes, with an intergroup interval of 5 minutes.Prior to and following the training period, the subjects engaged in a 10-minute warm-up and relaxation routine, with each session lasting approximately 40 minutes. Following each vibration training session, the subjects were required to complete the 'Active Fatigue Rating Scale - Level 5 Score Sheet [12] ' (Table 2), which enabled the researchers to assess their physical status before and after training. The next training load and programme were then adjusted according to the score of each subject. Following a four-week intervention period, the impact of the intervention was evaluated through a data analysis. Table 2 Active Fatigue Scale - Level 5 Score Scale score After training (judgement on this training) Before you start training (Judgement of last training) score 1 Feeling very heavy. No recovery, very tired, sore muscles 1 2 feel heavy Tiredness, muscle stiffness 2 3 Feels comfortable and just right A little tired, about to recover 3 4 relaxed resumption 4 5 It feels so easy. full recovery 5 Note: Total score: 2-4 points reduce the intensity of practice; 5-7 points continue to practice according to the programme; >7 points increase the intensity of practice appropriately. 1.2.2 Data processing The data on lower limb muscle strength of semi-elite athletes in short track speed skating were entered into an Excel spreadsheet before and after the intervention of the training programme and subsequently analysed using the Statistical Package for the Social Sciences (SPSS) version 23.0. All data were expressed as mean ± standard deviation. The data were tested for normal distribution using the Shapiro-Wilk test. Paired samples t-tests were employed to assess the impact of the intervention within groups, while one-way ANOVA was used to compare groups. The level of significance was set at 0.05, with a significant difference defined as P < 0.05 and a highly significant difference as P < 0.01. 2 Findings 2.1 Results of changes in peak knee joint moments before and after intervention As illustrated in Table 3, following four weeks of vibration training, the peak moments of the knee flexor and extensor muscle groups of both legs exhibited a notable enhancement compared to the initial measurements before training (P < 0.01). However, with the exception of the right extensor knee, the remaining peak moments before and after training did not demonstrate a statistically significant difference in the control subjects (P > 0.05). Table 4 reveals a significant difference (P < 0.01) in the peak moments of the flexor and extensor muscle groups of the knee joints of the three groups of subjects after four weeks. The post-hoc test indicates that the enhancement of the peak moments of the flexor muscle groups of the knee joints on both sides was more pronounced when the vibration frequency was 50 Hz. In the left extensor knee joint, the peak moments of the experimental group were observed to be greater than those of the control group. However, no significant difference was identified between the training effects of the 50 Hz and 30 Hz frequencies. In the right extensor knee joint, the peak moments of the experimental group were found to be significantly greater than those of the control group. Additionally, the training effect of the 50 Hz frequency was identified to be significantly superior to that of the 30 Hz frequency. Table 3 Peak moments of the knee joint before and after 60°/s intervention in the comparison group (unit:N-m; M±SD) groups pre-intervention post-intervention t P Left knee bend 30Hz 99±6.56 108.56±6.51 -5.71 <0.01 ## 50Hz 98.56±10.09 117.92±5.94 -7.77 <0.01 ## control subjects 95.08±5.92 96.2±6.10 -7.0 0.493 Right knee bend 30Hz 102.88±5.31 114.08±5.23 -6.81 <0.01 ## 50Hz 100.72±9.03 118.64±5.82 -10.50 <0.01 ## control subjects 96.52±6.36 98.64±6.40 -1.11 0.277 left knee extension 30Hz 204.28±8.35 214.68±7.72 -4.90 <0.01 ## 50Hz 202.04±23.15 214.84±8.32 -2.53 0.018 # control subjects 205.36±6.26 208.52±6.70 -1.60 0.125 right knee extension 30Hz 203.36±22.17 217.28±10.53 -3.55 0.002 ## 50Hz 205.12±9.18 222.08±7.59 -6.85 <0.01 ## control subjects 203±6.53 204.92±5.28 -2.69 0.013 # (Note: # is the result of paired samples t-test, P<0.05 means that the difference between the group after the intervention and before the intervention reaches a statistically significant level, and P<0.01 means that the group has a highly significant difference between the group after the intervention and before the intervention; * is the result of one-way ANOVA, P<0.05 means that there is a significant difference between the groups after the intervention, and P<0.01 means that the there is a highly significant difference between the post-intervention groups, the same below). Table 4 Peak knee moments after 60°/s intervention between the comparison groups (unit:N-m; M±SD) groups pre-intervention post-intervention F P after-test Left knee bend 30Hz(A) 99±6.56 108.56±6.51 77.462 <0.01 ** C<A<B ** 50Hz(B) 98.56±10.09 117.92±5.94 Control group (C) 95.08±5.92 96.2±6.10 Right knee bend 30Hz(A) 102.88±5.31 114.08±5.23 80.74 <0.01 ** C<A<B ** 50Hz(B) 100.72±9.03 118.64±5.82 Control group (C) 96.52±6.36 98.64±6.40 left knee extension 30Hz(A) 204.28±8.35 214.68±7.72 5.61 0.005 ** A<B; C<A ** ; C<B ** 50Hz(B) 202.04±23.15 214.84±8.32 Control group (C) 205.36±6.26 208.52±6.70 right knee extension 30Hz(A) 203.36±22.17 217.28±10.53 29.94 <0.01 ** A<B * ; C<A ** ; C<B ** 50Hz(B) 205.12±9.18 222.08±7.59 Control group (C) 203±6.53 204.92±5.28 2.2 Results of changes in peak knee power before and after the intervention As illustrated in Table 5, the subjects' knee flexor-extensor muscle groups exhibited a notable enhancement in peak power following four weeks of vibration training, when compared to the baseline measurements prior to training (P < 0.01). In contrast, the control group demonstrated a non-significant difference between the pre- and post-training assessments, with the exception of a notable increase in the peak power of the right flexor knee (P > 0.05). Table 6 reveals a significant difference in the peak power of the knee flexor and extensor muscle groups of the three subject groups after four weeks (P<0.01). Furthermore, the post hoc test revealed that the enhancement of the peak power of the bilateral knee flexor muscle groups and the left knee extensor muscle groups was more pronounced when the vibration frequency was 50 Hz. Additionally, the peak power of the right knee extensor muscle groups before and after right knee extension training was not significantly different from that of the 30 Hz group and the 50 Hz group despite the significant enhancement of peak power. A significant difference was observed between the 30 Hz and 50 Hz groups. Table 5 Within-group comparison of peak knee power before and after 180°/s intervention (unit:W; M±SD) groups pre-intervention post-intervention t P Left knee bend 30Hz 75.32±3.69 81±2.78 -7.508 <0.01 ## 50Hz 76±9.06 87.92±7.63 -7.580 <0.01 ## control subjects 79.84±9.83 81.28±8.01 -0.770 0.449 Right knee bend 30Hz 75.48±4.85 82.32±5.48 -6.282 <0.01 ## 50Hz 72.84±3.56 87.08±4.51 -12.374 <0.01 ## control subjects 76.88±6.23 77.64±6.40 -2.282 0.032 # left knee extension 30Hz 128.68±13.59 136.84±10.09 -5.801 <0.01 ## 50Hz 133.16±9.50 147.20±9.70 -11.141 <0.01 ## control subjects 131.24±8.98 133.32±8.25 -1.067 0.297 right knee extension 30Hz 129.40±14.34 145.32±9.93 -7.182 <0.01 ## 50Hz 132.52±11.29 150.28±8.32 -11.076 <0.01 ## control subjects 130.24±11.92 132.20±10.05 -0.606 0.550 Table 6 Between-group comparison of peak knee power after 180°/s intervention (unit:W; M±SD) groups pre-intervention post-intervention F P after-test Left knee bend 30Hz(A) 75.32±3.69 81±2.78 8.843 <0.01 ** C<B ** ; A<B ** 50Hz(B) 76±9.06 87.92±7.63 Control group (C) 79.84±9.83 81.28±8.01 Right knee bend 30Hz(A) 75.48±4.85 82.32±5.48 18.319 <0.01 ** C<A<B ** 50Hz(B) 72.84±3.56 87.08±4.51 Control group (C) 76.88±6.23 77.64±6.40 left knee extension 30Hz(A) 128.68±13.59 136.84±10.09 14.793 <0.01 ** A<B ** ; C<A; C<B ** 50Hz(B) 133.16±9.50 147.20±9.70 Control group (C) 131.24±8.98 133.32±8.25 right knee extension 30Hz(A) 129.40±14.34 145.32±9.93 24.345 <0.01 ** A<B; C<A ** ; C<B ** 50Hz(B) 132.52±11.29 150.28±8.32 Control group (C) 130.24±11.92 132.20±10.05 2.3 Results of changes in total knee joint function before and after intervention As illustrated in Table 7, following four weeks of whole-body vibration training, the total work of both the knee flexor and extensor muscle groups of the subjects exhibited a notable increase compared to the pre-training period (P < 0.01). Conversely, no statistically significant difference was observed in the total work of the left flexor and right extensor knees of the subjects in the control group between the pre- and post-training periods (P > 0.05). Table 8 reveals a significant difference in the total work of the flexor-extensor muscle groups of both knees in all three groups of subjects after four weeks (P < 0.01). However, no significant difference was observed in the effect of the frequencies of 30 Hz and 50 Hz on the total work of the flexor knee joints. Table 7 Total work of the knee joint before and after 180°/s intervention in the comparison group (unit:J; M±SD) groups pre-intervention post-intervention t P Left knee bend 30Hz 84.56±6.81 91.16±5.74 -11.051 <0.01 ## 50Hz 84.44±4.42 93.40±3.99 -13.141 <0.01 ## control subjects 83.60±4.98 85.68±4.41 -1.566 0.130 Right knee bend 30Hz 84.24±7.87 93.80±5.98 -14.99 <0.01 ## 50Hz 85.20±4.25 96.48±4.58 -37.939 <0.01 ## control subjects 85.44±3.00 87.80±4.44 -2.293 0.031 # left knee extension 30Hz 136.20±3.30 148.08±6.08 -10.722 <0.01 ## 50Hz 135.32±2.87 149.20±4.05 -22.101 <0.01 ## control subjects 135.64±2.61 138.64±2.66 -4.575 <0.01 ## right knee extension 30Hz 140.64±9.57 151.64±10.15 -15.016 <0.01 ## 50Hz 136.52±2.80 156.60±3.92 -26.148 <0.01 ## control subjects 138.04±3.30 139.60±3.20 -1.615 0.119 Table 8 Total knee joint work after 180°/s intervention between the comparison groups (unit: J; M±SD) groups pre-intervention post-intervention F P after-test Left knee bend 30Hz(A) 84.56±6.81 91.16±5.74 17.326 <0.01 ** C<A ** ; C<B ** 50Hz(B) 84.44±4.42 93.40±3.99 Control group (C) 83.60±4.98 85.68±4.41 Right knee bend 30Hz(A) 84.24±7.87 93.80±5.98 19.385 <0.01 ** C<A ** ; C<B ** 50Hz(B) 85.20±4.25 96.48±4.58 Control group (C) 85.44±3.00 87.80±4.44 left knee extension 30Hz(A) 136.20±3.30 148.08±6.08 41.723 <0.01 ** C<A ** ; C<B ** 50Hz(B) 135.32±2.87 149.20±4.05 Control group (C) 135.64±2.61 138.64±2.66 right knee extension 30Hz(A) 140.64±9.57 151.64±10.15 44.582 <0.01 ** C<A<B ** 50Hz(B) 136.52±2.80 156.60±3.92 Control group (C) 138.04±3.30 139.60±3.20 3 Discussion and analysis 3.1 Effect of 4 weeks of vibration training at different frequencies on lower limb maximal strength in semi-elite short track speed skaters In the process of random contraction, the most powerful capacity demonstrated by the human muscle is the maximum force. In this study, the peak moment is defined as the maximum moment value of the knee flexor and extensor muscle groups of short track speed skating students during exercise. This measurement can be used to assess the maximum muscle strength and absolute strength level of the knee muscle groups in these athletes. In this study, the peak moment measured at an angular velocity of 60°/s was employed to quantify the maximum strength of the knee muscles of the short track speed skating students. The athletes' training feedback was obtained through the 'Active Fatigue Score Scale - Level 5 Score Scale'. Following a four-week vibration training programme, the peak moments of the knee flexors and extensors of both legs exhibited a significant increase compared to the pre-training measurements. In contrast, the control subjects demonstrated no significant improvement in the peak moments of their knee joints before and after the training period. This suggests that the vibration frequency of 30 Hz and 50 Hz was higher than before the training, and that the peak moments of the knee joints were higher than before the training. It can be stated that vibration training with frequencies of 30 Hz and 50 Hz and an amplitude of 2 mm can demonstrably enhance maximal knee joint strength in semi-elite short track speed skaters.This finding is consistent with the experimental results of whole-body vibration training for volleyball players by Wu C C et al [13] . The excitation of the α motor neuron and γ motor neuron can cause skeletal muscle and intraclavicular muscle contraction, respectively. Vibration stimulation promotes muscle clavicle excitation, and the sensory information conveyed through the afferent nerve conduction to the α and γ motor neuron can cause more motor neuron and muscle fibre recruitment, forming a virtuous cycle. This results in continuous enhancement of muscle contraction. The findings of the study conducted by Marinho and colleagues indicated that whole body vibration training did not result in a notable enhancement in muscle strength and quadriceps thickness in renal transplant recipients [14] . This outcome may be attributed to the discrepancies in the results arising from the varying intensities of the training loads and the diverse health profiles of the subjects. A comparison of the effects of vibration training at different frequencies on the subjects revealed that the 50 Hz frequency had a more significant effect on the enhancement of the maximum strength of the knee flexor muscle group. Furthermore, Liu et al [15] found that vibration training has a significant advantage on the activation level of the neuromuscular system, which improves the muscle strength of the lower limbs by increasing the number of motor units recruited. The findings of this study demonstrated that, in comparison to other frequencies, whole-body vibration training at 50 Hz resulted in a more pronounced enhancement in the peak moments of the bilateral knee flexor and right knee extensor muscle groups, thereby indicating a superior efficacy in increasing the maximum strength of the knee joint. 3.2 Effects of 4 weeks of vibration training at different frequencies on lower limb quick strength in semi-elite short track speed skaters Rapid strength can be defined as the ability of a muscle to exert force rapidly, emphasising both power and speed. The concept of rapid strength can be defined as the rapid release of energy exhibited by a group of muscles. This is typically quantified as the product of muscle contraction force and contraction speed. The concept of fast power refers to the rapid release of energy exhibited by a muscle group, which is typically quantified as the product of muscle contractile force and contractile speed. In this study, peak power at 180°/s was employed to assess alterations in rapid power of knee muscle groups following four weeks of vibration training at varying frequencies. It was observed that after four weeks of vibration training, the peak power of knee flexors and extensors of both legs exhibited a marked increase compared to the initial measurements. The impact of joint muscle group training was more pronounced in the 50 Hz group, whereas the peak power of the knee joints in the control group remained largely unchanged after four weeks of training. This suggests that the peak power of the knee joints in the control group did not undergo a significant alteration over the four-week period. The majority of subjects exhibited no significant changes, indicating that vibration training with vibration frequencies of 30 Hz and 50 Hz and an amplitude of 2 mm has a notable impact on the rapid power development of the knee joints of semi-elite athletes in short track speed skating. This finding is consistent with the impact of whole body vibration (WBV) training on lower limb performance, which has been demonstrated to enhance lower limb performance indicators such as maximal isometric strength, deep squat jump, squat jump, floor jump and power endurance. This conclusion was reached by Haleva [9] , who conducted an intervention study to investigate the influence of WBV training on lower limb performance in a cohort of 24 healthy male physical education students. A comparison of the peak power of the knee joints of the three groups after four weeks of vibration training intervention revealed that a vibration frequency of 50 Hz was more effective than 30 Hz in enhancing the rapid power of the bilateral knee flexor muscle groups and the left knee extensor muscle group. Enhancement of motor neurons can increase the mobility of the muscles during exercise, which is beneficial for rapid muscle strength enhancement. A motor unit is defined as an alpha motor neuron and the muscle fibres it innervates, which collectively constitute the fundamental unit of muscle contraction. The excitability of motor neurons enables the recruitment of slow motor units from smaller cell bodies and fast motor units from larger cell bodies during muscle contraction, in accordance with the principle of recruitment size. The observed strength enhancement may be attributed to the kinetic change of the muscle fibres or muscle bundles during contraction [16] . Vibratory stimuli prompt the rapid recruitment of fast motor units with high excitation thresholds by the muscles. Conversely, when examined through a biomechanical lens, the acceleration generated by vibratory stimulation markedly amplifies the degree of stimulation received by proprioceptors. This alteration prompts an increase in the number of synaptic nerve conduction pathways engaged in the vibration-contraction reflex of the organism, resulting in the activation of motor units at varying excitatory thresholds and the recruitment of a larger pool of motor units for participation in the work. Consequently, the muscular nervous system is fully and optimally regulated, resulting in enhanced muscle responsiveness and contractility, as well as an increase in muscle cross-sectional area [17] .Similarly, Danxuan Cao et al. [6] proposed that whole-body vibration training enhances explosive power by augmenting tendon complex stiffness and optimising the storage of elastic potential energy. This, in turn, facilitates improved neuromuscular conduction and elongates the cycle. 3.3 Effects of 4 weeks of vibration training at different frequencies on lower limb strength endurance in semi-elite short track speed skaters The term "strength endurance" is used to describe the ability of a muscle to function in a sustained manner against an external load. This is evidenced by the length of time a muscle can continuously perform a contraction within a specified timeframe until it is completely fatigued or maintains a specific 1RM percentage of weight [18] .The term 'total work' is used to describe the work done by muscle contraction. This can be used to assess the muscle endurance of muscles during exercise, with the numerical value increasing in line with the number of repetitions and load weight. The findings of this experimental study demonstrated that the total work of both the knee flexor and extensor muscle groups of the subjects in the experimental group exhibited a notable enhancement, indicating that vibration training exerts a contributory influence on the improvement of knee strength endurance in semi-elite athletes engaged in short track speed skating. This outcome aligns with the results reported by Cai C M [19] et al.A comparison of the total work values between the three groups before and after the intervention revealed that vibration training affects the improvement of knee muscle endurance. However, the effect of the two frequencies, 30Hz and 50Hz, on knee flexor muscle group endurance was not found to be significantly different. This may be due to the relatively short time period of the experiment, which differs from the results of previous studies. Furthermore, muscle resonance is regarded as a benign manifestation of the resonance phenomenon that occurs within the human body. This phenomenon is one of the mechanisms through which whole-body vibration training improves the neuromuscular system. It can be categorised as a distinct form of vibration [20] . The research of Carlucci et al. [21] is worthy of note. The research demonstrated that at the resonant frequency, due to the existence of the maximum displacement between the organs and skeletal structures of the human body, the repeated accumulation of resonance can produce kinetic energy accumulation, which can be released at a specific period of time to enhance the ability of muscle contraction to do work. This process results in the relevant body tissues producing biodynamic strain and the muscle tendons also undergoing vibration and continuous energy metabolism [22] . This improves the maximum exercise capacity of the body and is conducive to the improvement of athletic performance. 4 Conclusions A four-week vibration training programme incorporating different frequencies resulted in a significant improvement in muscle strength in the knee joints of semi-elite short track speed skaters. The vibration frequency of 50 Hz demonstrated superior outcomes in terms of maximal and rapid strength when the amplitude was 2 mm, compared to the 30 Hz frequency. Declarations Acknowledgements Not applicable. Author contributions Qianrong Qi(Proposing a thesis topic, designing the thesis framework, writing the thesis), Yuanyuan Gao(Presenting the thesis topic and guiding the revision of the thesis). Funding the Applied Basic Research Project of Liaoning Province, (grant number 2022JH2/101300133); Liaoning Province General Higher Education Undergraduate Teaching Reform Research Project , (grant number 20230003). Data availability The datasets generated and/or analysed during the current study are not publicly available due [This study is still ongoing, and further discussions will be conducted in the future] but are available from the corresponding author on reasonable request. Ethics approval and consent to participate The survey was approved by the Ethics Committee of the Shenyang Sport University. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Author detail Harbin Sport University, Harbin 150008, China References Torres, A., et al., Relationship Between Strength And Power In Elite Short Track Speed Skaters. Medicine & Science in Sports & Exercise, 2022. Hartard, M., et al., Sex-specific response to whole-body vibration training: a randomized controlled trial. Biology of Sport, 2022. 39(1): p. 207-217. Lai, Z., et al., Comparison of whole-body vibration training and quadriceps strength training on physical function and neuromuscular function of individuals with knee osteoarthritis: A randomised clinical trial. Journal of Exercise Science & Fitness, 2021. 19(3): p. 150-157. Rittweger, J., Vibration as an exercise modality: how it may work, and what its potential might be. European Journal of Applied Physiology, 2010. 108(5): p. 877-904. Khademolhosseini, N., et al., The immediate effectiveness of whole-body vibration with the modified push-up position on neurocognitive parameters in overheads athletes with and without scapular dyskinesis. Sport sciences for health, 2023. 19(3): p. 949-957. Cao Danxuan et al, Application effect and mechanism of action of whole body vibration training. Journal of Wuhan Institute of Physical Education, 2023. 57(8): p. 92-100. Oliveira, L.C., R.G. Oliveira and D.A.A. Pires-Oliveira, Effects of whole body vibration on bone mineral density in postmenopausal women: a systematic review and meta-analysis. Osteoporosis International, 2016. 27(10): p. 2913-2933. Fiorilli, G., et al., The optimal whole body vibration frequency effects on postural responses in soccer players. Sport Sciences for Health, 2020. 16(3): p. 435-442. Haleva, Y., et al., Effect of whole-body vibration training with two different vibration amplitudes on lower limb performance. German Journal of Exercise and Sport Research, 2023. 53(2): p. 155-162. Swann, C., A. Moran and D. Piggott, Defining elite athletes: Issues in the study of expert performance in sport psychology. Psychology of Sport & Exercise, 2015. 16: p. 3-14. Nawayseh, N., et al., Effect of gender on the biodynamic responses to vibration induced by a whole-body vibration training machine. Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2019. 233(3): p. 383-392. Fu Chufan, Effects of deep squat class training in vibration state on lower limb muscle strength and morphology in male bodybuilders, 2019, Wuhan Institute of Physical Education. Wu, C.C., et al., The acute effects of whole body vibration stimulus warm-up on skill-related physical capabilities in volleyball players. Scientific Reports, 2021. 11(1). A, P.E.M.M., et al., Effects of whole-body vibration on muscle strength, quadriceps muscle thickness and functional capacity in kidney transplant recipients: A randomized controlled trial. Journal of Bodywork and Movement Therapies, 2021. 26: p. 101-107. Liu, Y., Y. Fan and X. Chen, Effects of whole-body vibration training in static and dynamic semi-squat patterns on the lower limb muscle activity. Scientific Reports, 2023. 13(1). Rubio Arias, J.Á., et al., Effects of whole‐body vibration training on calf muscle function during maximal isometric voluntary contractions. Scandinavian Journal of Medicine & Science in Sports, 2021. 31(6): p. 1268-1275. Centner, C., et al., Effects of Whole-Body Vibration Training and Blood Flow Restriction on Muscle Adaptations in Women: A Randomized Controlled Trial. Journal of strength and conditioning research, 2020. 34(3): p. 603-608. Yuan Yan, Neuromuscular Adaptation Characteristics of Weighted Vibration Strength Training and Its Mechanisms, 2013, Shanghai Institute of Physical Education. Cai, Z., et al., Effects of whole body vibration training combined with blood flow restriction on muscle adaptation. Eur J Sport Sci, 2021. 21(2): p. 204-212. Liu, S. M. et al. Advances in rehabilitation mechanisms of whole-body vibration training in severe chronic obstructive pulmonary disease. Chinese Journal of Respiratory and Critical Care, 2023. 22(4): p. 289-294. Carlucci, F., et al., Older Age Is Associated with Lower Optimal Vibration Frequency in Lower-Limb Muscles During Whole-Body Vibration. American journal of physical medicine & rehabilitation, 2015. 94(7): p. 522-529. Zhijun Shi, Juntao Yan & Yamin Kong, Application of vibration therapy in rehabilitation and its influencing factors. Chinese Journal of Medical Physics, 2019. 36(1): p. 102-107. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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-5484550","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":384221322,"identity":"1a0d004c-4783-4920-9e93-efd2fdbdcaf0","order_by":0,"name":"Qianrong Qi","email":"","orcid":"","institution":"Harbin Sport University","correspondingAuthor":false,"prefix":"","firstName":"Qianrong","middleName":"","lastName":"Qi","suffix":""},{"id":384221324,"identity":"79cd3c2f-00bc-4a8b-bce8-82b3af91bcf9","order_by":1,"name":"Yuanyuan Gao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvklEQVRIiWNgGAWjYBACxobzHx//qJDg4SdaC3PjAWNjhjMWcpINxGphbz5gJs3YVmFscIBYLbxtB5KNC85IJG4+nryB4UfFNsJaJHsOHHw8o0IicduZZwWMPWduE9ZiOONgswEP0JZtN3IMmBnbiNBif/8xmwRvG9BhM4jVwthwjE0aqMXYQIJ4LWeYDWeckZCTAPrlIFF+AWphfPChoo6Hvz1544MfFURoQQIJxEcNQgupOkbBKBgFo2CEAAADWkMaMi1v5gAAAABJRU5ErkJggg==","orcid":"","institution":"Harbin Sport University","correspondingAuthor":true,"prefix":"","firstName":"Yuanyuan","middleName":"","lastName":"Gao","suffix":""}],"badges":[],"createdAt":"2024-11-19 14:53:30","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5484550/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5484550/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71884075,"identity":"08bed755-465b-4106-8105-cdf0d6cdd5b6","added_by":"auto","created_at":"2024-12-19 11:57:22","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":119479,"visible":true,"origin":"","legend":"\u003cp\u003eChanges in peak moments of knee joints before and after experiments in three groups of subjects\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5484550/v1/232c857b09c6359f2de50b72.png"},{"id":71884079,"identity":"c7c2fb9e-8421-4485-aab9-00581b74dafc","added_by":"auto","created_at":"2024-12-19 11:57:22","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":117338,"visible":true,"origin":"","legend":"\u003cp\u003ePeak power changes before and after the knee experiment in three groups of subjects\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5484550/v1/5ec239d79663b10511856133.png"},{"id":71884078,"identity":"bcb19067-e533-4b94-a484-cddea75172a8","added_by":"auto","created_at":"2024-12-19 11:57:22","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":132041,"visible":true,"origin":"","legend":"\u003cp\u003eChanges in total work of the knee joint before and after the experiment in three groups of subjects\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5484550/v1/670e79afd23ec872cef2c9e8.png"},{"id":73757903,"identity":"fcf33736-a9c9-4d84-b319-a6b3a729a1a4","added_by":"auto","created_at":"2025-01-14 10:54:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1084212,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5484550/v1/9cb1aa7e-cdaa-4d69-8f12-aeacacb52f2f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A study of the effects of vibration training at different frequencies on lower limb muscle strength in semi-elite short track speed skaters","fulltext":[{"header":"Introduction","content":"\u003cp\u003eShort-distance speed skating, also known as short track speed skating, is a sport that requires a high level of physical dominance, particularly within the class of speed-related activities. The competitive abilities of athletes in this field are significantly influenced by their physical fitness, technical abilities, and strategic proficiency. To excel in this sport, athletes must possess a rapid nerve impulse conduction speed, superior quality of strength, and the ability to adapt to the rapid movements and frequent changes in direction on the ice. Therefore, a strong foundation of lower limb muscle strength is essential for short-track speed skating athletes to achieve optimal performance\u003csup\u003e[1]\u003c/sup\u003e. Muscle strength can be defined as the body\u0026apos;s capacity to counteract resistance. The mechanical properties of muscle are primarily related to four key factors: the initial length of the muscle, the physiological cross-sectional area of the muscle, external stimuli, and the level of central activation.Whole body vibration training (WBVT) is a method of exercise that involves the human body in a specific position on a vibration platform. The vibration frequency, amplitude, time and other parameters can be adjusted to stimulate the muscles mechanically, thereby promoting the nervous system\u0026apos;s ability to regulate and enhance the human body\u0026apos;s motor functions. This type of training has been demonstrated to enhance muscle strength\u003csup\u003e[2]\u003c/sup\u003e,explosive strength\u003csup\u003e[3]\u003c/sup\u003eand balance in a relatively short period of time. Additionally, it has been shown to improve neurocognitive abilities by providing the athlete with an unstable environment\u003csup\u003e[4]\u003c/sup\u003e, which is then utilised to stimulate the proprioceptors, including the muscle and tendon plexus\u003csup\u003e[5]\u003c/sup\u003e.At present, the frequency of whole body vibration training is predominantly concentrated within the 20-50 Hz range, with the majority of training programmes lasting between four and eight weeks\u003csup\u003e[6]\u003c/sup\u003e.The primary objective is to enhance the maximum strength and explosive power of muscles, while also capitalising on the elastic potential energy of muscles. The efficacy of different frequencies in muscle strength training has been the subject of considerable research. While studies have demonstrated the effectiveness of a range of frequencies, including both medium and high frequencies and low frequencies, the optimal frequency for developing strength remains a topic of ongoing investigation\u003csup\u003e[7, 8]\u003c/sup\u003e. In this experiment, the vibration frequencies of medium-low (30 Hz) and medium-high (50 Hz) were used to conduct a four-week\u003csup\u003e[9]\u003c/sup\u003e training intervention under the condition of 2 mm amplitude. The aim was to compare the changes in lower limb muscle strength before and after the training in order to investigate the effects of whole-body vibration training on semi-elite athletes of short-track speed skating.It is anticipated that whole-body vibration training will provide a theoretical foundation for exercise training in short-track speed skating, while elucidating the optimal setting parameters to augment muscle strength.\u003c/p\u003e"},{"header":"1 Objects of study and methodology","content":"\u003cp\u003e1.1 research target\u003c/p\u003e\n\u003cp\u003ePrior to the commencement of the experiment, a total of 80 short-track speed skating semi-elite athletes were recruited. Following the screening process, 75 male short-track speed skating semi-elite athletes\u003csup\u003e[10]\u003c/sup\u003e from the Shenyang Sports Institute were selected as the experimental subjects (Table 1). Subsequently, a one-way ANOVA analysis was conducted on the subjects\u0026apos; basic information and pre-test results. The obtained indexes demonstrated no significant difference between the groups. Subsequently, a random grouping was conducted using the random number generator in SPSS (the fixed value was 20231010), resulting in the formation of three groups: a vibration frequency of 30Hz group comprising 25 individuals, a 50Hz group comprising 25 individuals, and a control group comprising 25 individuals. Inclusion criteria: subjects were required to be healthy, without a history of cardiovascular or cerebrovascular disease, and free from any recent muscle or joint injuries. Additionally, they were not permitted to have undergone any surgical procedures within the previous six months and were required to refrain from engaging in strenuous exercise for a minimum of 24 hours prior to the test. Furthermore, they were asked to abstain from consuming beverages containing caffeine, creatine, alcohol, and other stimulants, and were prohibited from taking any anabolic drugs, including protein powder, with the intention of increasing muscle strength. The study was approved by the Ethics Committee of the Shenyang Sport University. All subjects were novices in vibration training and provided informed consent prior to participation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 1 Subjects\u0026apos; basic information（M\u0026plusmn;SD）\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30 Hz group (n=25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003eGroup 50Hz (n=25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003eControl group (n=25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003eAge/years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e23.80\u0026plusmn;2.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e23.64\u0026plusmn;2.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e23.88\u0026plusmn;1.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.912\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003eHeight/cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e1.79\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e1.81\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e1.81\u0026plusmn;0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.860\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.428\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003eWeight/kg\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e79.68\u0026plusmn;7.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e83.12\u0026plusmn;7.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e82.43\u0026plusmn;9.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e1.122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.331\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e(Note: P\u0026lt;0.05 indicates a significant difference between the pre-intervention groups, and P\u0026lt;0.01 indicates a highly significant difference between the pre-intervention groups, same below.)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e1.2 Research methodology\u003c/p\u003e\n\u003cp\u003e1.2.1 Experimental programme\u003c/p\u003e\n\u003cp\u003eThe experimental period commenced on 30 October 2023 and concluded on 25 December 2023. During the aforementioned period, the subjects were introduced to the vibration training apparatus and isokinetic muscle testing system between the dates of 30 October and 3 November. Between the dates of 6 November and 12 November, the subjects underwent a de-warming process. The pre-experimental testing phase commenced on 13 November and concluded on 17 November. The vibration training intervention phase commenced on 21 November and concluded on 14 December. The post-experimental testing phase commenced on 18 December and concluded on 25 December, marking the conclusion of the experiment.\u003c/p\u003e\n\u003cp\u003eThe experiment was conducted at a fitness centre located on the ground floor of Feibing Hall, which is part of the Shenyang Institute of Physical Education.\u003c/p\u003e\n\u003cp\u003eThe test location is the isokinetic muscle strength test, which is conducted in the Science and Technology Building.The apparatus and equipment used in the experiment are as follows: The apparatus employed was a Power Plate Pro5 vibration trainer, in conjunction with an IsoMed 2000 isokinetic muscle strength testing system.\u003c/p\u003e\n\u003cp\u003ePrior to the commencement of this study, the athletes underwent a training period of one week. This included familiarisation with the vibration training equipment, the movements to be performed, and pre-experimental testing of lower limb muscle strength. It has been demonstrated that the development of a whole-body vibration training programme must consider the impact of gender. Consequently, this experiment was conducted with male subjects\u003csup\u003e[11]\u003c/sup\u003e.The requirements for whole-body vibration training action posture are as follows: the subject\u0026apos;s torso should be naturally leaning forward, with the hips and knees flexed to a semi-squatting position on the vibration platform (knee angle of approximately 120\u0026deg;). In order to maintain the subject\u0026apos;s head posture, the focus should be on the sign in front of the mark point, with the hands holding the handrail in vain, the two feet wider than the shoulder, the whole foot on the ground with the toes slightly outwardly spread. Each training session comprises three groups, with each group undergoing the training three times. The vibration frequency is 30Hz for the first group of 10 people and 50Hz for the second group of 10 people. Each vibration time is 30 seconds. The control group of 10 people performs the same length and posture of the semi-squatting action on the vibration platform, but without additional vibration stimulation. The three groups of subjects undergo sub-intervals of 1-3 minutes, with an intergroup interval of 5 minutes.Prior to and following the training period, the subjects engaged in a 10-minute warm-up and relaxation routine, with each session lasting approximately 40 minutes. Following each vibration training session, the subjects were required to complete the \u0026apos;Active Fatigue Rating Scale - Level 5 Score Sheet\u003csup\u003e[12]\u003c/sup\u003e\u0026apos; (Table 2), which enabled the researchers to assess their physical status before and after training. The next training load and programme were then adjusted according to the score of each subject. Following a four-week intervention period, the impact of the intervention was evaluated through a data analysis.\u003c/p\u003e\n\u003cp\u003eTable 2 Active Fatigue Scale - Level 5 Score Scale\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"98%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003escore\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003eAfter training\u003c/p\u003e\n \u003cp\u003e(judgement on this training)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003eBefore you start training\u003c/p\u003e\n \u003cp\u003e(Judgement of last training)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003escore\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003eFeeling very heavy.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003eNo recovery, very tired, sore muscles\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003efeel heavy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003eTiredness, muscle stiffness\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003eFeels comfortable and just right\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003eA little tired, about to recover\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003erelaxed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003eresumption\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003eIt feels so easy.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 31px;\"\u003e\n \u003cp\u003efull recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eNote: Total score: 2-4 points reduce the intensity of practice; 5-7 points continue to practice according to the programme; \u0026gt;7 points increase the intensity of practice appropriately.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e1.2.2 Data processing\u003c/p\u003e\n\u003cp\u003eThe data on lower limb muscle strength of semi-elite athletes in short track speed skating were entered into an Excel spreadsheet before and after the intervention of the training programme and subsequently analysed using the Statistical Package for the Social Sciences (SPSS) version 23.0. All data were expressed as mean \u0026plusmn; standard deviation. The data were tested for normal distribution using the Shapiro-Wilk test. Paired samples t-tests were employed to assess the impact of the intervention within groups, while one-way ANOVA was used to compare groups. The level of significance was set at 0.05, with a significant difference defined as P \u0026lt; 0.05 and a highly significant difference as P \u0026lt; 0.01.\u003c/p\u003e"},{"header":"2 Findings","content":"\u003cp\u003e2.1 Results of changes in peak knee joint moments before and after intervention\u003c/p\u003e\n\u003cp\u003eAs illustrated in Table 3, following four weeks of vibration training, the peak moments of the knee flexor and extensor muscle groups of both legs exhibited a notable enhancement compared to the initial measurements before training (P \u0026lt; 0.01). However, with the exception of the right extensor knee, the remaining peak moments before and after training did not demonstrate a statistically significant difference in the control subjects (P \u0026gt; 0.05). Table 4 reveals a significant difference (P \u0026lt; 0.01) in the peak moments of the flexor and extensor muscle groups of the knee joints of the three groups of subjects after four weeks. The post-hoc test indicates that the enhancement of the peak moments of the flexor muscle groups of the knee joints on both sides was more pronounced when the vibration frequency was 50 Hz. In the left extensor knee joint, the peak moments of the experimental group were observed to be greater than those of the control group. However, no significant difference was identified between the training effects of the 50 Hz and 30 Hz frequencies. In the right extensor knee joint, the peak moments of the experimental group were found to be significantly greater than those of the control group. Additionally, the training effect of the 50 Hz frequency was identified to be significantly superior to that of the 30 Hz frequency.\u003c/p\u003e\n\u003cp\u003eTable 3 Peak moments of the knee joint before and after 60\u0026deg;/s intervention in the comparison group (unit:N-m; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e99\u0026plusmn;6.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e108.56\u0026plusmn;6.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-5.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e98.56\u0026plusmn;10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e117.92\u0026plusmn;5.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-7.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e95.08\u0026plusmn;5.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e96.2\u0026plusmn;6.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-7.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.493\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e102.88\u0026plusmn;5.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e114.08\u0026plusmn;5.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e100.72\u0026plusmn;9.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e118.64\u0026plusmn;5.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-10.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e96.52\u0026plusmn;6.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e98.64\u0026plusmn;6.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.277\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e204.28\u0026plusmn;8.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e214.68\u0026plusmn;7.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-4.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e202.04\u0026plusmn;23.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e214.84\u0026plusmn;8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-2.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.018\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e205.36\u0026plusmn;6.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e208.52\u0026plusmn;6.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-1.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.125\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e203.36\u0026plusmn;22.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e217.28\u0026plusmn;10.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-3.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.002\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e205.12\u0026plusmn;9.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e222.08\u0026plusmn;7.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-6.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e203\u0026plusmn;6.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e204.92\u0026plusmn;5.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-2.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.013\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e(Note:\u003csup\u003e#\u003c/sup\u003e is the result of paired samples t-test, P\u0026lt;0.05 means that the difference between the group after the intervention and before the intervention reaches a statistically significant level, and P\u0026lt;0.01 means that the group has a highly significant difference between the group after the intervention and before the intervention; * is the result of one-way ANOVA, P\u0026lt;0.05 means that there is a significant difference between the groups after the intervention, and P\u0026lt;0.01 means that the there is a highly significant difference between the post-intervention groups, the same below).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 4 Peak knee moments after 60\u0026deg;/s intervention between the comparison groups (unit:N-m; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\" style=\"margin-right: calc(0%); width: 100%;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15px;\"\u003e\n \u003cp\u003eafter-test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e99\u0026plusmn;6.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e108.56\u0026plusmn;6.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e77.462\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e98.56\u0026plusmn;10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e117.92\u0026plusmn;5.94\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e95.08\u0026plusmn;5.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e96.2\u0026plusmn;6.10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e102.88\u0026plusmn;5.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e114.08\u0026plusmn;5.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e80.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e100.72\u0026plusmn;9.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e118.64\u0026plusmn;5.82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e96.52\u0026plusmn;6.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e98.64\u0026plusmn;6.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e204.28\u0026plusmn;8.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e214.68\u0026plusmn;7.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e5.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.005\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eA\u0026lt;B;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e202.04\u0026plusmn;23.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e214.84\u0026plusmn;8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e205.36\u0026plusmn;6.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e208.52\u0026plusmn;6.70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e203.36\u0026plusmn;22.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e217.28\u0026plusmn;10.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e29.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eA\u0026lt;B\u003csup\u003e*\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e205.12\u0026plusmn;9.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e222.08\u0026plusmn;7.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e203\u0026plusmn;6.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e204.92\u0026plusmn;5.28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e2.2 Results of changes in peak knee power before and after the intervention\u003c/p\u003e\n\u003cp\u003eAs illustrated in Table 5, the subjects\u0026apos; knee flexor-extensor muscle groups exhibited a notable enhancement in peak power following four weeks of vibration training, when compared to the baseline measurements prior to training (P \u0026lt; 0.01). In contrast, the control group demonstrated a non-significant difference between the pre- and post-training assessments, with the exception of a notable increase in the peak power of the right flexor knee (P \u0026gt; 0.05). Table 6 reveals a significant difference in the peak power of the knee flexor and extensor muscle groups of the three subject groups after four weeks (P\u0026lt;0.01). Furthermore, the post hoc test revealed that the enhancement of the peak power of the bilateral knee flexor muscle groups and the left knee extensor muscle groups was more pronounced when the vibration frequency was 50 Hz. Additionally, the peak power of the right knee extensor muscle groups before and after right knee extension training was not significantly different from that of the 30 Hz group and the 50 Hz group despite the significant enhancement of peak power. A significant difference was observed between the 30 Hz and 50 Hz groups.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 5 Within-group comparison of peak knee power before and after 180\u0026deg;/s intervention (unit:W; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e75.32\u0026plusmn;3.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e81\u0026plusmn;2.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-7.508\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e76\u0026plusmn;9.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e87.92\u0026plusmn;7.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-7.580\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e79.84\u0026plusmn;9.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e81.28\u0026plusmn;8.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-0.770\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.449\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e75.48\u0026plusmn;4.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e82.32\u0026plusmn;5.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-6.282\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e72.84\u0026plusmn;3.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e87.08\u0026plusmn;4.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-12.374\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e76.88\u0026plusmn;6.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e77.64\u0026plusmn;6.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-2.282\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.032\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e128.68\u0026plusmn;13.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e136.84\u0026plusmn;10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-5.801\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e133.16\u0026plusmn;9.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e147.20\u0026plusmn;9.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-11.141\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e131.24\u0026plusmn;8.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e133.32\u0026plusmn;8.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-1.067\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.297\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e129.40\u0026plusmn;14.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e145.32\u0026plusmn;9.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-7.182\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e132.52\u0026plusmn;11.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e150.28\u0026plusmn;8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-11.076\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e130.24\u0026plusmn;11.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e132.20\u0026plusmn;10.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-0.606\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.550\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 6 Between-group comparison of peak knee power after 180\u0026deg;/s intervention (unit:W; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15px;\"\u003e\n \u003cp\u003eafter-test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e75.32\u0026plusmn;3.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e81\u0026plusmn;2.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e8.843\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eA\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e76\u0026plusmn;9.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e87.92\u0026plusmn;7.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e79.84\u0026plusmn;9.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e81.28\u0026plusmn;8.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e75.48\u0026plusmn;4.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e82.32\u0026plusmn;5.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e18.319\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e72.84\u0026plusmn;3.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e87.08\u0026plusmn;4.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e76.88\u0026plusmn;6.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e77.64\u0026plusmn;6.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e128.68\u0026plusmn;13.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e136.84\u0026plusmn;10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e14.793\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eA\u0026lt;B\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;A;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e133.16\u0026plusmn;9.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e147.20\u0026plusmn;9.70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e131.24\u0026plusmn;8.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e133.32\u0026plusmn;8.25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e129.40\u0026plusmn;14.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e145.32\u0026plusmn;9.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e24.345\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 15px;\"\u003e\n \u003cp\u003eA\u0026lt;B;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e132.52\u0026plusmn;11.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e150.28\u0026plusmn;8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e130.24\u0026plusmn;11.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e132.20\u0026plusmn;10.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e2.3 Results of changes in total knee joint function before and after intervention\u003c/p\u003e\n\u003cp\u003eAs illustrated in Table 7, following four weeks of whole-body vibration training, the total work of both the knee flexor and extensor muscle groups of the subjects exhibited a notable increase compared to the pre-training period (P \u0026lt; 0.01). Conversely, no statistically significant difference was observed in the total work of the left flexor and right extensor knees of the subjects in the control group between the pre- and post-training periods (P \u0026gt; 0.05). Table 8 reveals a significant difference in the total work of the flexor-extensor muscle groups of both knees in all three groups of subjects after four weeks (P \u0026lt; 0.01). However, no significant difference was observed in the effect of the frequencies of 30 Hz and 50 Hz on the total work of the flexor knee joints.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 7 Total work of the knee joint before and after 180\u0026deg;/s intervention in the comparison group (unit:J; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e84.56\u0026plusmn;6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e91.16\u0026plusmn;5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-11.051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e84.44\u0026plusmn;4.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e93.40\u0026plusmn;3.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-13.141\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e83.60\u0026plusmn;4.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e85.68\u0026plusmn;4.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-1.566\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.130\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e84.24\u0026plusmn;7.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e93.80\u0026plusmn;5.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-14.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e85.20\u0026plusmn;4.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e96.48\u0026plusmn;4.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-37.939\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e85.44\u0026plusmn;3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e87.80\u0026plusmn;4.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-2.293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.031\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e136.20\u0026plusmn;3.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e148.08\u0026plusmn;6.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-10.722\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e135.32\u0026plusmn;2.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e149.20\u0026plusmn;4.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-22.101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e135.64\u0026plusmn;2.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e138.64\u0026plusmn;2.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-4.575\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 16px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e30Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e140.64\u0026plusmn;9.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e151.64\u0026plusmn;10.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-15.016\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e50Hz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e136.52\u0026plusmn;2.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e156.60\u0026plusmn;3.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-26.148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e##\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003econtrol subjects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e138.04\u0026plusmn;3.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e139.60\u0026plusmn;3.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e-1.615\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16px;\"\u003e\n \u003cp\u003e0.119\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 8 Total knee joint work after 180\u0026deg;/s intervention between the comparison groups (unit: J; M\u0026plusmn;SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003egroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003epre-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003epost-intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eafter-test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eLeft knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e84.56\u0026plusmn;6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e91.16\u0026plusmn;5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e17.326\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 13px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e84.44\u0026plusmn;4.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e93.40\u0026plusmn;3.99\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e83.60\u0026plusmn;4.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e85.68\u0026plusmn;4.41\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eRight knee bend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e84.24\u0026plusmn;7.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e93.80\u0026plusmn;5.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e19.385\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 13px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e85.20\u0026plusmn;4.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e96.48\u0026plusmn;4.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e85.44\u0026plusmn;3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e87.80\u0026plusmn;4.44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eleft knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e136.20\u0026plusmn;3.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e148.08\u0026plusmn;6.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e41.723\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 13px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u003csup\u003e**\u003c/sup\u003e ;\u003c/p\u003e\n \u003cp\u003eC\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e135.32\u0026plusmn;2.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e149.20\u0026plusmn;4.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e135.64\u0026plusmn;2.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e138.64\u0026plusmn;2.66\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 11px;\"\u003e\n \u003cp\u003eright knee extension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e30Hz(A)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e140.64\u0026plusmn;9.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e151.64\u0026plusmn;10.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 9px;\"\u003e\n \u003cp\u003e44.582\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.01\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 13px;\"\u003e\n \u003cp\u003eC\u0026lt;A\u0026lt;B\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003e50Hz(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e136.52\u0026plusmn;2.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e156.60\u0026plusmn;3.92\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14px;\"\u003e\n \u003cp\u003eControl group (C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e138.04\u0026plusmn;3.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003e139.60\u0026plusmn;3.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"3 Discussion and analysis","content":"\u003cp\u003e3.1 Effect of 4 weeks of vibration training at different frequencies on lower limb maximal strength in semi-elite short track speed skaters\u003c/p\u003e\n\u003cp\u003eIn the process of random contraction, the most powerful capacity demonstrated by the human muscle is the maximum force. In this study, the peak moment is defined as the maximum moment value of the knee flexor and extensor muscle groups of short track speed skating students during exercise. This measurement can be used to assess the maximum muscle strength and absolute strength level of the knee muscle groups in these athletes. In this study, the peak moment measured at an angular velocity of 60\u0026deg;/s was employed to quantify the maximum strength of the knee muscles of the short track speed skating students. The athletes\u0026apos; training feedback was obtained through the \u0026apos;Active Fatigue Score Scale - Level 5 Score Scale\u0026apos;. Following a four-week vibration training programme, the peak moments of the knee flexors and extensors of both legs exhibited a significant increase compared to the pre-training measurements. In contrast, the control subjects demonstrated no significant improvement in the peak moments of their knee joints before and after the training period. This suggests that the vibration frequency of 30 Hz and 50 Hz was higher than before the training, and that the peak moments of the knee joints were higher than before the training. It can be stated that vibration training with frequencies of 30 Hz and 50 Hz and an amplitude of 2 mm can demonstrably enhance maximal knee joint strength in semi-elite short track speed skaters.This finding is consistent with the experimental results of whole-body vibration training for volleyball players by Wu C C et al\u003csup\u003e[13]\u003c/sup\u003e. The excitation of the \u0026alpha; motor neuron and \u0026gamma; motor neuron can cause skeletal muscle and intraclavicular muscle contraction, respectively. Vibration stimulation promotes muscle clavicle excitation, and the sensory information conveyed through the afferent nerve conduction to the \u0026alpha; and \u0026gamma; motor neuron can cause more motor neuron and muscle fibre recruitment, forming a virtuous cycle. This results in continuous enhancement of muscle contraction. The findings of the study conducted by Marinho and colleagues indicated that whole body vibration training did not result in a notable enhancement in muscle strength and quadriceps thickness in renal transplant recipients\u003csup\u003e[14]\u003c/sup\u003e. This outcome may be attributed to the discrepancies in the results arising from the varying intensities of the training loads and the diverse health profiles of the subjects.\u003c/p\u003e\n\u003cp\u003eA comparison of the effects of vibration training at different frequencies on the subjects revealed that the 50 Hz frequency had a more significant effect on the enhancement of the maximum strength of the knee flexor muscle group. Furthermore, Liu et al\u003csup\u003e[15]\u003c/sup\u003e found that vibration training has a significant advantage on the activation level of the neuromuscular system, which improves the muscle strength of the lower limbs by increasing the number of motor units recruited. The findings of this study demonstrated that, in comparison to other frequencies, whole-body vibration training at 50 Hz resulted in a more pronounced enhancement in the peak moments of the bilateral knee flexor and right knee extensor muscle groups, thereby indicating a superior efficacy in increasing the maximum strength of the knee joint.\u003c/p\u003e\n\u003cp\u003e3.2 Effects of 4 weeks of vibration training at different frequencies on lower limb quick strength in semi-elite short track speed skaters\u003c/p\u003e\n\u003cp\u003eRapid strength can be defined as the ability of a muscle to exert force rapidly, emphasising both power and speed. The concept of rapid strength can be defined as the rapid release of energy exhibited by a group of muscles. This is typically quantified as the product of muscle contraction force and contraction speed. The concept of fast power refers to the rapid release of energy exhibited by a muscle group, which is typically quantified as the product of muscle contractile force and contractile speed. In this study, peak power at 180\u0026deg;/s was employed to assess alterations in rapid power of knee muscle groups following four weeks of vibration training at varying frequencies. It was observed that after four weeks of vibration training, the peak power of knee flexors and extensors of both legs exhibited a marked increase compared to the initial measurements. The impact of joint muscle group training was more pronounced in the 50 Hz group, whereas the peak power of the knee joints in the control group remained largely unchanged after four weeks of training. This suggests that the peak power of the knee joints in the control group did not undergo a significant alteration over the four-week period. The majority of subjects exhibited no significant changes, indicating that vibration training with vibration frequencies of 30 Hz and 50 Hz and an amplitude of 2 mm has a notable impact on the rapid power development of the knee joints of semi-elite athletes in short track speed skating. This finding is consistent with the impact of whole body vibration (WBV) training on lower limb performance, which has been demonstrated to enhance lower limb performance indicators such as maximal isometric strength, deep squat jump, squat jump, floor jump and power endurance. This conclusion was reached by Haleva\u003csup\u003e[9]\u003c/sup\u003e, who conducted an intervention study to investigate the influence of WBV training on lower limb performance in a cohort of 24 healthy male physical education students.\u003c/p\u003e\n\u003cp\u003eA comparison of the peak power of the knee joints of the three groups after four weeks of vibration training intervention revealed that a vibration frequency of 50 Hz was more effective than 30 Hz in enhancing the rapid power of the bilateral knee flexor muscle groups and the left knee extensor muscle group. Enhancement of motor neurons can increase the mobility of the muscles during exercise, which is beneficial for rapid muscle strength enhancement. A motor unit is defined as an alpha motor neuron and the muscle fibres it innervates, which collectively constitute the fundamental unit of muscle contraction. The excitability of motor neurons enables the recruitment of slow motor units from smaller cell bodies and fast motor units from larger cell bodies during muscle contraction, in accordance with the principle of recruitment size. The observed strength enhancement may be attributed to the kinetic change of the muscle fibres or muscle bundles during contraction\u003csup\u003e[16]\u003c/sup\u003e. Vibratory stimuli prompt the rapid recruitment of fast motor units with high excitation thresholds by the muscles. Conversely, when examined through a biomechanical lens, the acceleration generated by vibratory stimulation markedly amplifies the degree of stimulation received by proprioceptors. This alteration prompts an increase in the number of synaptic nerve conduction pathways engaged in the vibration-contraction reflex of the organism, resulting in the activation of motor units at varying excitatory thresholds and the recruitment of a larger pool of motor units for participation in the work. Consequently, the muscular nervous system is fully and optimally regulated, resulting in enhanced muscle responsiveness and contractility, as well as an increase in muscle cross-sectional area\u003csup\u003e[17]\u003c/sup\u003e.Similarly, Danxuan Cao et al.\u003csup\u003e[6]\u003c/sup\u003e proposed that whole-body vibration training enhances explosive power by augmenting tendon complex stiffness and optimising the storage of elastic potential energy. This, in turn, facilitates improved neuromuscular conduction and elongates the cycle.\u003c/p\u003e\n\u003cp\u003e3.3 Effects of 4 weeks of vibration training at different frequencies on lower limb strength endurance in semi-elite short track speed skaters\u003c/p\u003e\n\u003cp\u003eThe term \u0026quot;strength endurance\u0026quot; is used to describe the ability of a muscle to function in a sustained manner against an external load. This is evidenced by the length of time a muscle can continuously perform a contraction within a specified timeframe until it is completely fatigued or maintains a specific 1RM percentage of weight\u003csup\u003e[18]\u003c/sup\u003e.The term \u0026apos;total work\u0026apos; is used to describe the work done by muscle contraction. This can be used to assess the muscle endurance of muscles during exercise, with the numerical value increasing in line with the number of repetitions and load weight. The findings of this experimental study demonstrated that the total work of both the knee flexor and extensor muscle groups of the subjects in the experimental group exhibited a notable enhancement, indicating that vibration training exerts a contributory influence on the improvement of knee strength endurance in semi-elite athletes engaged in short track speed skating. This outcome aligns with the results reported by Cai C M\u003csup\u003e[19]\u003c/sup\u003e et al.A comparison of the total work values between the three groups before and after the intervention revealed that vibration training affects the improvement of knee muscle endurance. However, the effect of the two frequencies, 30Hz and 50Hz, on knee flexor muscle group endurance was not found to be significantly different. This may be due to the relatively short time period of the experiment, which differs from the results of previous studies. Furthermore, muscle resonance is regarded as a benign manifestation of the resonance phenomenon that occurs within the human body. This phenomenon is one of the mechanisms through which whole-body vibration training improves the neuromuscular system. It can be categorised as a distinct form of vibration\u003csup\u003e[20]\u003c/sup\u003e. The research of Carlucci et al.\u003csup\u003e[21]\u003c/sup\u003e is worthy of note. The research demonstrated that at the resonant frequency, due to the existence of the maximum displacement between the organs and skeletal structures of the human body, the repeated accumulation of resonance can produce kinetic energy accumulation, which can be released at a specific period of time to enhance the ability of muscle contraction to do work. This process results in the relevant body tissues producing biodynamic strain and the muscle tendons also undergoing vibration and continuous energy metabolism\u003csup\u003e[22]\u003c/sup\u003e. This improves the maximum exercise capacity of the body and is conducive to the improvement of athletic performance.\u003c/p\u003e"},{"header":"4 Conclusions","content":"\u003cp\u003eA four-week vibration training programme incorporating different frequencies resulted in a significant improvement in muscle strength in the knee joints of semi-elite short track speed skaters. The vibration frequency of 50 Hz demonstrated superior outcomes in terms of maximal and rapid strength when the amplitude was 2 mm, compared to the 30 Hz frequency.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQianrong Qi(Proposing a thesis topic, designing the thesis framework, writing the thesis), Yuanyuan Gao(Presenting the thesis topic and guiding the revision of the thesis).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ethe Applied Basic Research Project of Liaoning Province, (grant number 2022JH2/101300133); Liaoning Province General Higher Education Undergraduate Teaching Reform Research Project , (grant number 20230003).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analysed during the current study are not \u0026nbsp;publicly available due [This study is still ongoing, and further discussions will \u0026nbsp;be conducted in the future] but are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe survey was approved by the Ethics Committee of the Shenyang Sport University.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor detail\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHarbin Sport University, Harbin 150008, China\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eTorres, A., et al., Relationship Between Strength And Power In Elite Short Track Speed Skaters. Medicine \u0026amp;amp; Science in Sports \u0026amp;amp; Exercise, 2022.\u003c/li\u003e\n\u003cli\u003eHartard, M., et al., Sex-specific response to whole-body vibration training: a randomized controlled trial. Biology of Sport, 2022. 39(1): p. 207-217.\u003c/li\u003e\n\u003cli\u003eLai, Z., et al., Comparison of whole-body vibration training and quadriceps strength training on physical function and neuromuscular function of individuals with knee osteoarthritis: A randomised clinical trial. Journal of Exercise Science \u0026amp; Fitness, 2021. 19(3): p. 150-157.\u003c/li\u003e\n\u003cli\u003eRittweger, J., Vibration as an exercise modality: how it may work, and what its potential might be. European Journal of Applied Physiology, 2010. 108(5): p. 877-904.\u003c/li\u003e\n\u003cli\u003eKhademolhosseini, N., et al., The immediate effectiveness of whole-body vibration with the modified push-up position on neurocognitive parameters in overheads athletes with and without scapular dyskinesis. Sport sciences for health, 2023. 19(3): p. 949-957.\u003c/li\u003e\n\u003cli\u003eCao Danxuan et al, Application effect and mechanism of action of whole body vibration training. Journal of Wuhan Institute of Physical Education, 2023. 57(8): p. 92-100.\u003c/li\u003e\n\u003cli\u003eOliveira, L.C., R.G. Oliveira and D.A.A. Pires-Oliveira, Effects of whole body vibration on bone mineral density in postmenopausal women: a systematic review and meta-analysis. Osteoporosis International, 2016. 27(10): p. 2913-2933.\u003c/li\u003e\n\u003cli\u003eFiorilli, G., et al., The optimal whole body vibration frequency effects on postural responses in soccer players. Sport Sciences for Health, 2020. 16(3): p. 435-442.\u003c/li\u003e\n\u003cli\u003eHaleva, Y., et al., Effect of whole-body vibration training with two different vibration amplitudes on lower limb performance. German Journal of Exercise and Sport Research, 2023. 53(2): p. 155-162.\u003c/li\u003e\n\u003cli\u003eSwann, C., A. Moran and D. Piggott, Defining elite athletes: Issues in the study of expert performance in sport psychology. Psychology of Sport \u0026amp; Exercise, 2015. 16: p. 3-14.\u003c/li\u003e\n\u003cli\u003eNawayseh, N., et al., Effect of gender on the biodynamic responses to vibration induced by a whole-body vibration training machine. Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2019. 233(3): p. 383-392.\u003c/li\u003e\n\u003cli\u003eFu Chufan, Effects of deep squat class training in vibration state on lower limb muscle strength and morphology in male bodybuilders, 2019, Wuhan Institute of Physical Education.\u003c/li\u003e\n\u003cli\u003eWu, C.C., et al., The acute effects of whole body vibration stimulus warm-up on skill-related physical capabilities in volleyball players. Scientific Reports, 2021. 11(1).\u003c/li\u003e\n\u003cli\u003eA, P.E.M.M., et al., Effects of whole-body vibration on muscle strength, quadriceps muscle thickness and functional capacity in kidney transplant recipients: A randomized controlled trial. Journal of Bodywork and Movement Therapies, 2021. 26: p. 101-107.\u003c/li\u003e\n\u003cli\u003eLiu, Y., Y. Fan and X. Chen, Effects of whole-body vibration training in static and dynamic semi-squat patterns on the lower limb muscle activity. Scientific Reports, 2023. 13(1).\u003c/li\u003e\n\u003cli\u003eRubio Arias, J.\u0026Aacute;., et al., Effects of whole‐body vibration training on calf muscle function during maximal isometric voluntary contractions. Scandinavian Journal of Medicine \u0026amp; Science in Sports, 2021. 31(6): p. 1268-1275.\u003c/li\u003e\n\u003cli\u003eCentner, C., et al., Effects of Whole-Body Vibration Training and Blood Flow Restriction on Muscle Adaptations in Women: A Randomized Controlled Trial. Journal of strength and conditioning research, 2020. 34(3): p. 603-608.\u003c/li\u003e\n\u003cli\u003eYuan Yan, Neuromuscular Adaptation Characteristics of Weighted Vibration Strength Training and Its Mechanisms, 2013, Shanghai Institute of Physical Education.\u003c/li\u003e\n\u003cli\u003eCai, Z., et al., Effects of whole body vibration training combined with blood flow restriction on muscle adaptation. Eur J Sport Sci, 2021. 21(2): p. 204-212.\u003c/li\u003e\n\u003cli\u003eLiu, S. M. et al. Advances in rehabilitation mechanisms of whole-body vibration training in severe chronic obstructive pulmonary disease. Chinese Journal of Respiratory and Critical Care, 2023. 22(4): p. 289-294.\u003c/li\u003e\n\u003cli\u003eCarlucci, F., et al., Older Age Is Associated with Lower Optimal Vibration Frequency in Lower-Limb Muscles During Whole-Body Vibration. American journal of physical medicine \u0026amp; rehabilitation, 2015. 94(7): p. 522-529.\u003c/li\u003e\n\u003cli\u003eZhijun Shi, Juntao Yan \u0026amp; Yamin Kong, Application of vibration therapy in rehabilitation and its influencing factors. Chinese Journal of Medical Physics, 2019. 36(1): p. 102-107.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"vibration training, different frequencies, short track speed skating, lower limb muscle strength","lastPublishedDoi":"10.21203/rs.3.rs-5484550/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5484550/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe aim of this study is to examine the impact of lower limb muscle strength in semi-elite athletes engaged in short track speed skating through the lens of different frequency vibration training. The methodology employed in this study is as follows: The study employs an experimental methodology. Subsequent to the screening process, a total of 75 male semi-elite short track speed skaters were selected from the Shenyang Institute of Physical Education. The participants were randomly assigned to one of three groups: a 30 Hz frequency vibration group comprising 25 individuals, a 50 Hz frequency vibration group comprising 25 individuals, and a control group comprising 25 individuals. The experimental group underwent the intervention on two occasions per week, with three groups participating on each occasion. The total duration of the intervention was four weeks, with an amplitude of 2mm. Each session comprised 30 seconds of whole-body vibration training. The control group comprised 25 individuals who performed the same duration and posture of semi-squatting movement on the vibration platform, but without additional vibration stimulation. The maximum strength, rapid strength, and strength endurance of the knee flexors and extensors during centripetal contraction were evaluated both before and after the intervention. The results are presented in the following manner: (1) Maximum power: the peak moments of the knee flexor and extensor muscle groups of both legs of the subjects exhibited a notable enhancement in comparison to the values observed prior to the training period (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The vibration frequency of 50 Hz demonstrated a more pronounced impact on the improvement of the peak moments of the knee flexor muscle groups on both sides. (2) Rapid power: the 50Hz vibration frequency was observed to have a more significant enhancement effect on the peak power of the bilateral knee flexor muscle groups and the left knee extensor muscle groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). (3) Muscular endurance: a significant difference was observed in the total work of the subjects' bilateral knee flexor and extensor muscle groups with different frequencies of vibration stimulation (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), with a highly significant difference noted in the total work of the left knee flexor muscle group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). It can be concluded that four weeks of vibration training at different frequencies can significantly improve the muscle strength of the knee joints in semi-elite short track speed skaters. Furthermore, the results demonstrate that a vibration frequency of 50 Hz is more effective than 30 Hz in terms of maximal and rapid strength when the amplitude is 2 mm.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e","manuscriptTitle":"A study of the effects of vibration training at different frequencies on lower limb muscle strength in semi-elite short track speed skaters","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-19 11:57:18","doi":"10.21203/rs.3.rs-5484550/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6961915b-5215-4827-a8e2-7d49c8e7f48c","owner":[],"postedDate":"December 19th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-01-14T10:54:48+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-19 11:57:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5484550","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5484550","identity":"rs-5484550","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}