在动态疲劳任务后,电气引起的同位素平脚曲收缩受损不如自愿
Michael T Paris1, Sohum V Kulkarni1, Charles L Rice
1School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, ON, CANADA.
Medicine and science in sports and exercise
|June 28, 2023
概括
动态疲劳任务减少了自愿肌肉功率比电力引起的功率更多,这表明中央和外围疲劳. 在电力引起的收缩中,恢复速度更快,扭矩和速度损害的负载依赖贡献.
科学领域:
- 运动生理学 运动生理学
- 肌肉生理学 肌肉生理学
- 生物力学 生物力学
背景情况:
- 评估疲劳诱导的功率损失通常依赖于同度扭矩,这可能不能准确地代表动态性能.
- 了解中央和外围对疲劳的贡献对于准确的性能评估至关重要.
研究的目的:
- 为了比较自愿和电气唤起的峰值功率及其决定因素在动态疲劳任务之前和之后.
- 调查中心和外围因素对动态收缩性表现和恢复的影响.
主要方法:
- 参与者进行了动态的足底曲收缩,以诱导疲劳.
- 在疲劳之前和之后,在不同的负载 (20%和40%的等比扭矩) 下评估了自愿和电气引起的收缩.
- 测量了峰值功率,动态扭矩,速度和速度发展率 (RVD).
主要成果:
- 自发性收缩显示高峰功率和RVD (~40-50%) 与疲劳后立即引起的电气收缩 (~25-35%) 相比,减少了更多.
- 电力唤起功率和RVD恢复到基线的速度 (<5分钟) 比自愿收缩更快,在10分钟内仍然处于低压状态.
- 动态扭矩和速度的损坏导致功率损失,速度在40%的负载下受到更大的影响.
结论:
- 疲劳后动态收缩性能的减少涉及中央和外围过程.
- 电气引起的收缩在疲劳时提供了更完整的收缩功能的测量.
- 扭矩和速度损害对功率损失的相对贡献取决于收缩负载.
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