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四头骨的表面电动图频率特征在连续的高和低扭矩等比式膝盖延伸到瞬间故障之间存在差异
Jonathan Murphy1, Emma Hodson-Tole2, Andrew D Vigotsky3
1Solent University, Department of Sport and Health, Southampton, UK.
概括
在异比膝盖延伸过程中表面电肌图 (sEMG) 的波形分析揭示了明显的肌肉疲劳模式. 低扭矩运动会增加所有频率,而高扭矩运动会使频率更低,显示出不同的适应.
科学领域:
- 生物力学 生物力学
- 运动生理学 运动生理学
- 电力生理学 电力生理学
背景情况:
- 表面电肌图 (sEMG) 通常用于评估运动期间的肌肉负荷.
- 对于sEMG平均/中位频率的传统分析可能会忽略运动任务之间的微妙的电生理学差异.
- 需要先进的信号处理技术来捕捉微妙的肌肉激活模式.
研究的目的:
- 为了研究四头四肢sEMG信号的电生理学差异,在高和低扭矩等比式膝盖延伸之间进行暂时失效.
- 为了将基于波纹的分析与传统的频率分析进行比较,以表征肌肉疲劳.
主要方法:
- 十名经过阻力训练的雄性在70% (高扭矩) 和30% (低扭矩) 的最大自发收缩 (MVC) 时进行了对称膝盖延伸,直到失败.
- sEMG从巨大的中间体,大腿直体和巨大的横体中记录下来.
- 波段变换分析被应用于sEMG信号,以及平均频率分析.
主要成果:
- 平均信号频率在瞬间故障时,在两种扭矩条件中显示出相似的变化.
- 波形分析显示频率组件的适应不同:低扭矩增加了所有组件,而高扭矩增加了低频和降低了高频组件.
- 由于这些不同的适应,在低扭矩试验结束时,sEMG特性在条件之间趋同.
结论:
- 波形分析比传统的频率分析更详细地了解肌肉疲劳.
- 在高和低扭矩疲劳收缩之间,肌肉纤维招募和神经控制的不同适应发生.
- 需要进一步的研究,以阐明驱动这些运动期间观察到的频率特征的具体因素.
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