膝盖屈曲器的最大次疲劳奇特收缩改变了腿部的非个人表现
Flavio Da Silva1, Enzo Piponnier1, Baptiste Corcelle1
1Université Côte d'Azur, LAMHESS, France.
Heliyon
|August 23, 2023
概括
奇特的运动疲劳会损害立即之后的位置感知精度,影响中枢和外围神经肌肉功能. 24小时后,观察到位置感和神经肌肉功能完全恢复.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 运动学 运动学
- 运动医学 运动医学
背景情况:
- 众所周知,古怪的收缩会引起显著的肌肉疲劳.
- 自身感,或位置感,对于运动控制至关重要,并且可能会受到疲劳的影响.
- 异常诱导的疲劳对位置感觉的影响,特别是使用新的位置指向任务,需要进一步研究.
研究的目的:
- 评估异常运动引起的疲劳对膝关节位置感的直接和长时间影响.
- 研究神经肌肉疲劳 (中心和外围) 与位置感知精度变化之间的关系.
- 使用定位指向任务来量化疲劳性炼后自身感觉的改变.
主要方法:
- 15名健康成年人进行了单边膝盖曲器异常运动方案,以诱导最大同位数扭矩减少20%.
- 神经肌肉功能的评估是通过最大自愿的同度收缩和电动肌肉刺激进行的.
- 在40°和70°的膝盖曲之前,曲后 (POST) 和曲后24小时 (POST24) 评估了位置感.
主要成果:
- 运动 (POST) 后立即观察到自愿激活水平和唤起的双倍幅度的显著降低,这表明中央和外围疲劳.
- 在POST时,定位指向错误显著增加,参与者高估了四肢延伸.
- 神经肌肉功能和位置感受在POST24之前恢复到基线水平.
结论:
- 异常诱导的疲劳严重损害了膝关节位置感知精度,与中部和外围神经肌肉疲劳有关.
- 观察到的位置感的缺陷表明中枢神经系统处理动感信息的变化.
- 在24小时内,经过令人疲劳的异常运动协议后,位置感完全恢复.
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