自主激活最大的单指和所有手指的动力握握收缩
Daanish Chauhan1, Tivyan Aruneethan1, Tina Tran1
1School of Kinesiology and Health Science, Faculty of Health, York University, Toronto, Ontario, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|November 27, 2024
概括
当所有手指握在一起时,与单个手指的强度相比,手指的强度会降低. 这项研究发现,缺陷并不是由于自愿激活率较低,女性表现出更大的力量缺陷.
科学领域:
- 人类生理学 人类生理学
- 生物力学 生物力学
- 神经肌肉功能的神经肌肉功能
背景情况:
- 众所周知的现象是,在多指握力收缩过程中,单个手指的力量输出减少.
- 这种力量缺陷往往归因于自发动机单元激活的减少.
研究的目的:
- 调查四指握力收缩期间手指力减少是否是由自愿激活的下降引起的.
- 为了比较单指和全指收缩之间的力量产生和自愿激活.
主要方法:
- 15名年轻成年人进行了食指和所有手指的最大自愿收缩 (MVC).
- 一个定制的动力计在自愿和电气引起的收缩过程中记录了个体手指的力量.
- 介质和部神经的电刺激评估了各种MVC强度的自愿激活.
主要成果:
- 指指在孤立状态下产生的力量大约比所有手指收缩时多25%.
- 在单指和全指MVC之间没有观察到自愿激活的显著差异.
- 在女性 (34%) 与男性 (18%) 相比,食指力缺陷更大,独立于自愿激活.
结论:
- 在多位数收缩过程中减少的手指曲力并不能通过改变的自愿激活来解释.
- 所有手指的收缩都显示出单个手指的近最大自发激活.
- 由于女性的力量缺陷较大,因此需要进一步研究基于性别的神经肌肉差异.
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