振动结合负重刺激对下肢表面肌电均方根振幅的影响:基于4种刺激下半蹲起提踵练习

摘要

背景:肌电图能通过反映记录肌肉活动特征参数来评价锻炼效果,振动练习是传统负重训练的最佳补充,近年来研究单纯性振动训练对下肢表面肌电影响的文献较多,但振动结合负重练习对下肢表面肌电影响的研究较少.目的:通过表面肌电从肌肉工作原理的微观层面来探讨振动结合负重刺激对下肢肌肉的影响.方法:以8名健康大学生为研究对象,分别附加4种不同刺激:频率45 Hz振动结合45%最大力量负重、频率45 Hz振动结合60%最大力量负重、频率50 Hz振动结合45%最大力量负重和频率50 Hz振动结合60%最大力量负重,完成每组1 min的10次半蹲起提踵练习,共3组,间隔2 h以上.结果与结论:不同振动结合负重刺激对被测肌肉表面肌电均方根振幅的影响非常有显著性意义(P<0.01).与其他3种刺激比,频率50 Hz振动结合45%最大力量负重刺激作用下的肌肉表面肌电均方根振幅的均值最大,尤其是腓肠肌内侧.除了半腱肌外,4种刺激对股直肌、胫骨前肌和腓肠肌内侧肌肉表面肌电均方根振幅的影响效果差异有显著性意义(P≤0.05);除频率50 Hz振动结合45%最大力量负重刺激外,其他3种刺激对股直肌、胫骨前肌、半腱肌和腓肠肌内侧肌肉表面肌电均方根振幅的影响效果差异有显著性意义(P≤0.05).与其他3种刺激相比,频率50 Hz振动结合45%最大力量负重刺激对被测肌肉激活程度的效果更好.不同振动结合负重刺激对同一肌肉运动单位的激活效果是不同的,适宜的刺激可能产生更好激活效果;同一刺激针对不同部位的肌肉运动单位的激活效果是不同的,可能是因为要求刺激与肌肉本身的特质相匹配.%BACKGROUND: The surface electromyography can evaluate the effect of exercise by recording the parameters of muscle activities, and vibration exercise is the best supplement to traditional weight training. More research focuses on the effect of simple vibration training on the surface electromyography of lower limbs, but the influence of vibration combined with weight-bearing training is poorly understood.OBJECTIVE: To study the effect of vibration combined with load on the surface electromyography of lower limbs at the micro level of muscle working principle.METHODS: Eight healthy college students were recruited, and subjected to four different stimulations: vibration (45 Hz) combined with load (45% one repetition maximum (IRM)); vibration (45 Hz) combined with load (60% 1RM); vibration (50 Hz) combined with load (45% 1RM); vibration (50 Hz) combined with load (60% 1RM), followed by semi-squat exercise with the heel lifting, 10 times/minute, for 3 courses with more than 2 hours in between.RESULTS AND CONCLUSION: Different vibrations combined with loads made significant difference on the root mean square amplitude of the surface electromyography (P < 0.01), and there was a significantly increased root mean square amplitude in the vibration (50 Hz) combined with load (45% 1RM), especially at the medial gastrocnemius. The four kinds of stimulations made significant different effects on the surface electromyography of rectus femoris, tibialis anterior, and medial gastrocnemius, except semitendinosus (P ≤ 0.05). Moreover, the effect showed significant difference among different stimulations except vibration (50 Hz) combined with load (45% 1RM) (P ≤ 0.05). Compared with the other three stimulations, vibration (50 Hz) combined with load (45% 1RM) exerted better effect on the muscular activation. To conclude, different vibrations combined with loads exert different effects on the motor unit of same neuromuscular activity, and a suitable stimulation may produce better effect. Besides, the same stimulus for the motor unit of different neuromuscular activities produces different effects, which may match to the muscle nature.