应用表面肌电图评定乒乓球运动员的上肢肌疲劳

Surface electromyography for evaluating the upper-limb fatigue of ping-pong athletes

目的:对北京市优秀乒乓球运动员进行提拉弧圈球训练时握拍上肢主要做功肌肉表面肌电(surfaceelectromyography,sEMG)信号进行分析,利用时、频域指标的变化来评价上肢肌疲劳情况。方法:北京市乒乓球队7名男性运动员,进行乒乓球训练的主要内容为提拉弧圈球训练,采集准备活动后训练开始与训练结束前各20min的握拍上肢:肱三头肌、肱二头肌、肱桡肌、三角肌、腕屈肌和腕伸肌肌电信号,利用Megawin软件进行平均功率频率(meanpowerfrequency,MPF),中位频率(medianfrequency,MF),均方根振幅(root-mean-square,RMS)的分析,两个实验测试阶段的频域和时域值的差异性利用t检验进行统计处理。结果:第2阶段所测六块肌肉的MPF,MF均比第1阶段的明显降低(P<0.001),具有非常显著性差异;第2阶段与第1阶段的RMS值相比,所测肌肉的RMS值变化趋势不稳定。结论:频域指标MPF,MF可较敏感地反映乒乓球训练上肢肌肉功能状况,可作为评价肌肉动态负荷水平的生理学指标。

AIM: To analyze the surface electromyography(sEMG) signal of working upper limb muscle of ping pang athletes during lifting and drawing loop training, and evaluate the muscle functional status by studying the time and frequency characteristics change.METHODS: Seven Beijing ping pong team athletes were involved in this study, the sEMG signals including brachial triceps muscle, Biceps brachii muscle, Brachioradialis muscle, deltoid muscle, wrist flexor and extensor muscle of upper limb were recorded during ping pong training at the first and the last 20 minutes, and the major training was lifting and drawing loop training. The mean power frequency (MPF) ,median frequency (MF)and root mean square(RMS)change were analyzed with Megawin software in this two phases. The difference in the frequency and time value were analyzed statistically with t test.RESULTS:Compared with the beginning phase, the MPF and MF in the ending phase were decreased significantly(P< 0.001), but the changing tendency of RMS was unstable in different muscles.CONCLUSION: MPF and MF can sensitively reflect the muscle functional status of upper limbs during ping pong training, which are regarded as the good predictors for evaluating dynamic muscle function.