单侧肢体电刺激训练对双侧肢体力量和表面肌电的影响

Bilateral effects of unilateral electromyostimulation training on strength and surface myoelectric signal

目的:运用表面肌电技术观察单侧肢体电刺激训练对双侧肢体力量和表面肌电(sEMG)的影响,为临床单侧肢体损伤、外科术后等引起的肌萎缩的康复治疗以及建立床边客观的训练效果评定方法提供依据。方法:选择18—30岁未经专项体育训练的青年男性30例为实验对象,随机分为电刺激组,随意等长收缩组和对照组。采用重复等长收缩模式对右侧胫骨前肌进行6周的电刺激和随意力量训练。训练前后进行双侧肌肉力量和sEMG测试。结果:电刺激组(右33.6%,左27.8%)和随意等长收缩组(右37.4%,左28.5%)训练侧和未训练侧的足背屈肌肉力量在训练后均有显著提高,与对照组(右1.3%,左0.8%)有显著性差异(P<0.05);随意等长收缩组(右100.4%,左59.4%)与电刺激组(右68.1%,左57.7%)双侧肌电平均振幅(AEMG)均有明显变化,并与对照组(右5.04%,左-4.07%)有显著性差异(P<0.05);肌肉不同等长用力和肌电振幅之间表现出非线性的关系,以指数y=43.762(9.584)t分布。结论:6周单侧肢体电刺激训练和随意等长收缩训练不仅能够明显的提高训练侧的肢体力量,亦能提高对侧未受训练肢体的肌肉力量;训练导致的力量增长与使用表面肌电观察到的AEMG的变化有关;肌肉力量和肌电振幅之间表现出非线性的关系,可以利用肌电振幅与相对力量的关系(y=43.762(9.584)t,在力量测试中评估受试者的用力程度,为临床康复训练提供理论依据和测试评价手段。

Objective： To investigate the bilateral effects of unilateral electromyostimulation（EMS） training on muscle strength and surface myoelectric signal by surface electro myogram（sEMG） technique.Method： Thirty healthy male volunteers, aged 18-30 years, were randomly assigned into three groups （n=10 each）： EMS group, voluntary isometric contraction （VIM） group, and control （CON） group. The patients of EMSand VIM groups were trained the right legs, 3 sessions per week for 6 weeks. All groups were tested for muscle strength and sEMG pre- and post-training period.Result： Repeated measures ANOVA with Bonferroni adjustment revealed significant increase （P 〈 0.05） in dorsiflexion maximal voluntary contraction（MVC） of both legs in both EMS group（33.6% on the right leg, 27.8% on theleft） and VIM group（37.4%, 28.5%）, while CON group showed no significant increase （1.3%, 0.8%, respectively）. The average amplitude of electromyogram（AEMG） improved significantly in both limbs of EMS group （P〈0.05;right 68.1%, left 57.7%） and in VIM group（100.4%, 59.4%）, CON group（5.04%,-4.07%） （P〉0.05）, respectively.There was non-linear relationship between muscle strength and amplitude of surface myoelectric signal during isometric contraction, y=43.762（9.584）^t.Conclusion：The results indicated that unilateral EMS and voluntary isometric training could significantly improve muscular strength not only in the exercised legs,but also in the contralateral limbs. The results also indicated thatthe increased AEMG was responsible for much of the improved strength.A non-linear relationship between muscle strength and sEMG amplitude, could probably use to assess subjects＇ exertion test for clinical rehabilitation.Author＇s address Shaanxi Institute of Sport Science, Xi＇an, Shanxi Province, 710065