扭矩发展速度和关节角度与被动肌肉度的关联
1Department of Sport Science and Research, Japan Institute of Sports Sciences (JISS), 3-15-1, Nishigaoka, Kita-Ku, Tokyo, 115-0056, Japan. ryosuke.ando@jpnsport.go.jp.
European journal of applied physiology
|April 17, 2024
概括
扭矩发展速率 (RTD) 在脚侧侧曲角度较大. 相对的RTD与脊椎曲位置的中部胃角 (MG) 度相关,表明长度依赖的肌肉特性.
科学领域:
- 生物力学 生物力学
- 人体生理学 人体生理学
- 肌肉骨研究 研究
背景情况:
- 扭矩发展速度 (RTD) 是肌肉功能的关键指标.
- 了解RTD如何随肌肉长度而变化以及它与被动性质的关系,对于优化性能和预防伤害至关重要.
研究的目的:
- 通过统计比较不同脚角度的相对RTD (平脚曲,中性,背部曲).
- 为了探索相对RTD和各种脚角度的被动中间胃角硬度 (MG) 之间的相关性.
主要方法:
- 22名健康的参与者在15°,0°和-15°的脚角度进行了爆炸性的同度足部曲.
- 相对RTD计算为时间-扭矩曲线的斜率正常化至最大扭矩.
- 超声剪波弹性学测量了MG剪波速度 (SWV) 作为每个角度的被动刚度指数.
主要成果:
- 相对的RTD在15°显著增加,而在特定时间窗口的15°和0°相比,相对的RTD显著增加.
- 与0°和-15°相比,峰值扭矩在15°时较低.
- 相对RTD与MG硬度相关于-15° (背部曲),但不是在其他角度,在较长的肌肉长度 (0-100毫秒时间窗口) 观察到更强的相关性.
结论:
- 三肌肌群在平侧曲角度 (较短的肌肉长度) 呈现出较大的相对RTD.
- 相对RTD与被动MG度有显著的关系,特别是在背部的角度 (较长的肌肉长度).
- 这些发现突显了肌肉长度和被动机械特性对爆炸力产生的影响.
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