肌肉抗张的历史依赖性抵抗力在小,体位相关的运动前运动后仍然很高
Brian C Horslen1,2, Gregory N Milburn3, Kyle P Blum2,4
1Department of Kinesiology and Health Sciences, University of Waterloo, Waterloo, ON, Canada, N2L 3G1.
The Journal of experimental biology
|September 4, 2023
概括
肌肉硬,或抵抗伸展,基于先前运动史 (运动史依赖) 的变化. 大规模或频繁的运动显著降低了这种阻力,影响了平衡和姿势控制.
科学领域:
- 生物力学 生物力学
- 肌肉生理学 肌肉生理学
- 发动机控制器的控制器
背景情况:
- 内在的肌肉纤维阻力对于姿势控制至关重要,但其通过运动历史的调制尚未完全理解.
- 肌肉短距离硬性表现出史学依赖性 (thixotropy),随着激活和运动史而变化.
- 关于肌肉度如何随着姿势相关的伸展和激活特征而变化的数据有限.
研究的目的:
- 量化肌肉抵抗在单个,激活的肌肉纤维伸展的历史依赖.
- 为了研究姿势相关的伸展幅度和激活水平如何影响肌肉硬.
- 确定前期运动特征与随后的肌肉抵抗之间的关系.
主要方法:
- 在透的单个肌肉纤维上使用配对肌肉伸展范式.
- 多样化的调节拉伸缩短周期幅度和拉伸间隔.
- 测试了低,中,高肌肉纤维激活水平,测量了短距离硬度和总冲动.
主要成果:
- 肌肉阻力在小型空调延伸 (<1%L0) 和长时间间隔 (>1s) 中仍然很高,这是正常站立的典型特征.
- 阻力在较长的训练延伸 (>3%L0) 和短的间隔 (<0.1s) 时减弱了70%左右,模仿失衡.
- 硬度的提克索特洛普变化不仅仅是通过瞬间的肌肉力量来预测的.
结论:
- 肌肉纤维对伸展的抵抗性在很大程度上取决于历史.
- 肌肉阻力减弱的程度与之前运动的幅度和频率有关.
- 这些发现凸显了肌肉厚度如何在动态行为 (如姿势摇摆) 中大幅改变抵抗.
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