单侧肱二头肌不同收缩模式对对侧肱二头肌兴奋性的影响

The Effect of Unilateral Isotonic and Isometric Contraction of Biceps on Excitability of Contralateral Biceps

目的:探讨单侧肱二头肌在等张、等长情况下收缩对侧肱二头肌肌肉兴奋性的影响。方法:招募30例健康人,使用表面肌电测试仪观察一侧肱二头肌进行等张、等长收缩时,对侧肱二头肌的均方根振幅(RMS)变化。结果:左右侧肱二头肌表面肌电信号在静息和无负重下全范围屈伸肘关节时,两者均无显著性差异(P>0.05);左右侧肱二头肌RMS在对侧不同收缩情况下均呈显著性差异(P<0.001)。结论:单侧肱二头肌在等张和等长收缩时,对侧肱二头肌兴奋性也会出现短暂提高,后恢复静息水平。

Objective:To explore the excitability of unilateral biceps under isotonic and isometric contraction of contralateral biceps.Method:Thirty health volunteer were recruited,all of them were guided to perform isotonic and isometric contraction of bilateral biceps alternatively,with real time surface electromyography testing.The primary outcome was root mean square(RMS).Result:There was no significant difference on RMS of bilateral biceps under resting circumstance and full range contraction without weight(P>0.05).Whereas the RMS of bilateral biceps were increased under isotonic and isometric contraction of contralateral biceps(P<0.001).Conclusion:The unilateral isotonic and isometric contraction will transiently increase the excitability of contralateral biceps,however which will resume to resting level soon.