递增负重蹲跳与提踵时小腿三头肌表面肌电图信号比较

Comparison of Surface Electromyographic Muscle at Incremental Weight Squat Jump and Toe Raise

目的:通过对男大学生小腿三头肌在递增负重提踵和蹲跳动作时表面肌电(sEMG)信号的分析,探讨动作形式与神经肌肉活动方式之间的联系。方法:男大学生在不负重和30%、60%、80%、100%最大力量(1RM)负重下分别进行一次提踵和蹲跳动作,同时记录腓肠肌内侧头(GM)、外侧头(GL)和比目鱼肌(SO)向心收缩阶段的sEMG信号,比较各等级负重条件下两种动作运动时iEMG、MF和MPF等肌电指标的变化。结果:在进行负重提踵时,随着重量增加,GM、GL和SO表面肌电的iEMG均显著增加,但MF和MPF在不同负重等级完成动作时的差异不显著;在进行负重蹲跳时,各肌肉表面肌电信号的iEMG、MF和MPF在各级负重之间具有显著差异,其数值与重量的增加具有线性关系;在不负重提踵时各肌肉的iEMG值与蹲跳差异不显著,但大负重后显著高于蹲跳;MF和MPF值在不负重提踵时显著高于蹲跳,负重后其差异基本不显著。结论:在递增负重提踵和蹲跳动作时,小腿三头肌向心收缩阶段的sEMG信号表现存在差异,其所反映的神经肌肉控制方式不同,提示所完成动作的动力学特性如速度、多关节链等,可能会影响运动单位募集的方式。

Objective ： it is to analyze the surfaceelectromyographic （sEMG） signals of the triceps surae muscle at incremental weight squat jump and toe raise, to discuss the relationship between the kinetic properties of motion and the behaviour of electromyographic. Methods： sEMG signals of the soleus （SO）, gastrocnemius medialis （GM） and gastrocnemius lateralis （GL） muscles were recorded in 12 healthy male subjects, during the action of squat jump and toe raise at the weight 0, 30%, 60%, 80%, 100%, separately. The iEMG, MF and MPF were analyzed at each action and loads. Results： the iEMG of GM, GL and SO increased significantly along with the load; MFand MPF had no significant difference between each loads grade at weight toe raise. The iEMG, MF and MPF increased significantly while the load increased, and there was a positive linearity in these indexes of sEMG and the load at weight squat jump. The value of iEMG had no significant difference between squat jump and toe raise without load, however, the iEMG at toe raise was higher than squat jump with heavy load. At toe raise without load, the value of MF and MPF were higher than squat jump significantly, but had no significant difference with load. Conclusion： the pattern of sENG signal of the triceps sttrae muscle showed diversity at incremental weight squat jump and toe raise, which reflected the different patterns of neuromuscular control, indicating that the recruitment pattern of motor units might be affected by the kinetic properties such as velocity and multi-joint chains.