不同拉伸对下肢爆发力的急性影响

Acute Effects of Different Stretching on the Explosive Power of Lower Limbs

目的:探究动态拉伸、PNF拉伸、PNF+动态组合拉伸对下肢爆发力的急性影响,为运动员在赛前准备活动中选择合理的拉伸方式提供科学依据。方法:选取具有2年以上力量训练经验的17名男性受试者,采用被试内设计,在不同的4天内安排4次分别包含无拉伸、动态拉伸、PNF拉伸和组合拉伸的实验任务。实验流程为受试者慢跑5分钟后进行拉伸干预,结束即刻通过测力台进行CMJ测试获取纵跳高度和起跳功率数据以评价下肢爆发力,通过无线表面肌电测试仪同步记录CMJ过程中下肢肌肉的表面肌电信号,并通过测量不同肌群的最大肌力,结合CMJ指标进一步了解不同拉伸对爆发力的影响特点。采用单因素重复测量方差分析处理上述数据。结果:3种拉伸后即刻CMJ指标无明显变化;动态拉伸后即刻股外侧肌、腓肠肌内侧头和腓肠肌外侧头IEMG显著下降,股内侧肌IEMG显著上升;PNF拉伸后即刻股内侧肌、股外侧肌IEMG显著上升,股二头肌、腓肠肌外侧头IEMG显著下降;组合拉伸后即刻腓肠肌外侧头IEMG显著下降,股内侧肌IEMG显著上升。其余肌电活动均无显著变化。结论:适当拉伸可对下肢神经肌肉功能产生有利影响,具有提高下肢爆发力的潜在可能性,适合在爆发力类运动前进行练习。

Objectives:To investigate the acute effects of dynamic stretching,PNF stretching and PNF+dynamic combination stretching on the explosive power of lower limbs,and to provide scientific basis for athletes to choose reasonable stretching methods in pre-competition activities.Methods:A total of 17 male subjects with more than two years of strength training experience were selected and designed within the subjects.Four experimental tasks including no stretching,dynamic stretching,PNF stretching and combined stretching were arranged in different four days.The experimental process was as follows.The subjects were subjected to stretching intervention after jogging for 5 min.At the end of the experiment,CMJ test was carried out on the dynamometer to obtain the vertical jump height and take-off power data to evaluate the explosive force of the lower limb.The surface EMG signals of the lower limb muscles in the process of CMJ were synchronously recorded by the wireless surface EMG tester,and the maximum muscle strength of different muscle groups was measured.Combined with the CMJ index,the influence characteristics of different stretching on the explosive force were further understood.Analysis of variance with single factor repeated measures was used to analyze the above data.Results:There was no significant change in CMJ index immediately after three kinds of stretching.Immediately after dynamic stretching,IEMG of lateral femoral muscle,gastrocnemius medial head and lateral gastrocnemius decreased significantly,and IEMG of medial thigh muscle increased significantly;immediately after PNF stretching,IEMG of vastus medialis muscle,lateral femoral muscle increased significantly,while IEMG of biceps femoris and lateral gastrocnemius decreased significantly;IEMG of the lateral head of lateral gastrocnemius decreased significantly immediately after combination stretching,while IEMG of vastus medialis muscle increased significantly.There were no significant changes in other EMG activities.Conclusions:Appropriate stretching can have a beneficial effect on the neuromuscular function of lower limbs,which has the potential to improve the explosive force of lower limbs and is suitable for practice before explosive exercise.