肌肉摇摆质量动力学:自身频率依赖于活动,冲击强度和地面材料
Kasper B Christensen1, Michael Günther2,3, Syn Schmitt2,4
1Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany. kasper.christensen@inspo.uni-stuttgart.de.
Scientific reports
|November 10, 2023
概括
运动期间的肌肉振荡会受到冲击的影响. 活跃的老鼠肌肉 (GAS) 显示出比被动的肌肉更高的主导特异频率,其差异归因于肌-动因附着.
科学领域:
- 生物力学 生物力学
- 肌肉生理学 肌肉生理学
- 运动动力学 运动动力学
背景情况:
- 腿部运动中的肌肉在撞击地面时经历了缓和的振荡.
- 肌肉振荡的性质受到冲击条件的影响.
研究的目的:
- 为了研究激活状态在模拟地面接触期间对肌肉自身频率的影响.
- 为了确定撞击参数 (高度,表面) 对肌肉振荡的影响.
- 模拟肌肉度,并将其与观察到的自身频率联系起来.
主要方法:
- 孤立的老鼠胃半径 (GAS) 肌肉使用定制设备受到冲击.
- 肌肉在活跃 (完全激活) 和被动状态下进行了测试.
- 从不同的高度对不同的地面材料进行了冲击.
- 开发了一个3度自由度 (3DoF) 模型来估计肌肉硬度.
主要成果:
- 与被动的GAS肌肉 (139 Hz, 215 Hz, 286 Hz) 相比,活跃的GAS肌肉表现出明显更高的主导特征频率 (163 Hz, 265 Hz, 399 Hz).
- 无论是下降的高度还是地面材料都没有显著改变主动或被动GAS的固有频率.
- 3DoF模型准确地预测了实验特征频率,对于主动和被动状态都有小偏差.
结论:
- 肌肉激活状态在冲击过程中显著改变主导的自身频率.
- 活跃与被动肌肉特异频率的差异的主要原因是肌肉素头部-动蛋白附着.
- 在这个模型中,高度和表面材料等冲击参数对GAS肌肉自身频率的影响最小.
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