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低频疲劳对人类四头肌扭矩-转速关系的影响
Jon Herskind1,2, Anders Gravholt1,3, Lars G Hvid1,4
1Exercise Biology, Department of Public Health, Aarhus University, Aarhus, Denmark.
Journal of applied physiology (Bethesda, Md. : 1985)
|November 2, 2023
概括
低频疲劳在动态收缩期间显著减少最大肌肉力量和功率输出,而最大收缩速度基本上不受影响. 这项研究阐明了低频疲劳如何影响人体肌肉功能在各种速度.
科学领域:
- 人类生理学 人类生理学
- 肌肉疲劳导致肌肉疲劳.
- 生物力学 生物力学
背景情况:
- 低频疲劳 (LFF) 通常定义为电气引起的同度收缩中的减少力.
- 没有充分了解LFF对动态肌肉功能的影响,特别是扭矩-速度关系.
- 了解LFF的影响对于优化培训和康复策略至关重要.
研究的目的:
- 为了研究LFF对人类膝盖延伸器中电力引起的扭矩-速度关系的影响.
- 测量最大扭矩 (Fmax),最大收缩速度 (Vmax) 和最大功率 (Pmax) 的变化.
主要方法:
- 在异动力膝盖延伸中,使用15 Hz和50 Hz电刺激来建立扭矩-速度关系.
- 通过最大的自愿动态膝盖延伸 (5组10次重复) 诱导疲劳.
- 在疲劳之前和之后计算了力-速度参数 (Fmax,Vmax,Pmax) 和15:50 Hz的比率.
主要成果:
- 在疲劳后,最大扭矩 (Fmax) 在15 Hz (40%) 和50 Hz (15%) 均显著下降.
- 最大功率 (Pmax) 也在15 Hz (30%) 和50 Hz (10%) 下降,在较低频率下降更大.
- 最大收缩速度 (Vmax) 在任何刺激频率都没有显著变化.
结论:
- 疲劳收缩降低了刺激频率的Fmax和Pmax,表明LFF对整体力量和功率产生产生影响.
- 疲劳性协议对Vmax没有显著的影响,这表明保持了缩短速度.
- 在动态收缩过程中,LFF显然会影响功率输出,即使保持最大缩短速度.
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