刺激频率对扭矩和速度发展的早期和晚期相速的影响
Michael T Paris1,2, Alexander M Zero1, Charles L Rice1,3
1School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|June 20, 2024
概括
高电刺激频率对于早期扭矩和速度的发展至关重要. 然而,在同位素收缩过程中速度发展的速度取决于负载,没有负载的收缩比负载适度的收缩更大频率依赖.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 生物力学 生物力学
- 运动科学 运动科学
背景情况:
- 扭矩发展的早期速度 (RTD) 取决于神经肌肉激活速度.
- 速度发展率 (RVD) 的决定因素不太清楚,可能是负载依赖的.
- 很少有研究研究了刺激频率和RVD之间的关系.
研究的目的:
- 探索刺激频率和早期/晚期同位度RTD之间的关系.
- 研究刺激频率与早期/晚期同位素RVD之间的关系.
- 要确定负载如何影响刺激频率和RVD之间的关系.
主要方法:
- 16名娱乐活动参与者的膝盖延伸器在14个频率 (1-100赫兹) 上被刺激.
- 进行了同度和同位素 (无负荷和7.5%的MVC负荷) 收缩.
- 分析了RTD和RVD的早期 (0-50毫秒) 和晚期 (0-100毫秒) 阶段,使用西格功能拟合和双线回归.
主要成果:
- RTD和RVD显示出与刺激频率 (r2 > 0.96) 有着强烈的西格形关系.
- 与晚期相比,早期的同度RTD和未加载的同位素RVD的斜率较低,平原频率较高.
- 适度负载的同位素RVD在早期和晚期阶段表现出类似的反应,斜坡或平原频率没有显著差异.
结论:
- 早期的同度RTD和未加载的同位素RVD高度依赖于刺激频率.
- 同位素RVD对刺激频率的依赖受外部负载的影响.
- 特定任务的收缩负荷对于理解缩短速度的神经肌肉激活决定因素至关重要.
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