自发性收缩低估了在跳跃中肌肉活动的高峰期
David Alan Phillips1, Skylar Paletta2, Michael Perlet2
1College of Health, Program in Kinesiology, Oregon State University-Cascades, Bend, Oregon.
International biomechanics
|June 10, 2025
概括
最大的自愿同度收缩 (MVIC) 经常低估在跳跃期间的峰值肌肉激活. 这项研究量化了这种电肌图 (EMG) 规范化差异,揭示了关键下肢肌肉的显著低估.
科学领域:
- 生物力学 生物力学
- 人类运动科学科学 人类运动科学
- 运动生理学 运动生理学
背景情况:
- 最大自发同度收缩 (MVIC) 是将电肌图 (EMG) 数据正常化为%MVIC的标准.
- 最近的文献表明,在落地跳跃过程中会发生超极小肌肉激活,这质疑了MVIC的代表性.
- 低估肌肉激活峰值可能导致对生物力学数据的误解.
研究的目的:
- 量化MVIC和跳跃着陆期间最大激活之间的EMG振幅正常化差异.
- 为了确定MVIC是否准确地代表动态运动期间下肢肌肉的峰值肌肉激活.
主要方法:
- 16名参与者 (10名男性,6名女性) 进行了跳和MVIC.
- 在这两种条件下,EMG数据从9个下肢肌肉中收集.
- 从10个跳跃试验中获得的最大EMG振幅与MVIC值进行了比较.
主要成果:
- MVIC显著低估了最大肌肉激活率为71%-140%的直骨 femoris,广的中间体,中间的胃角,侧面的胃角,前腰和最大部.
- 对这些肌肉发现了统计学意义 (p < 0.05).
- 数据的变化阻止了对剩余肌肉的统计学上有意义的发现.
结论:
- 使用MVICs对EMG数据的规范化显著低估了在落地跳跃着陆期间最大肌肉激活.
- 这些发现支持现有的文献,表明MVICs并不完全代表动态任务中的峰值激活.
- 对跳跃等动态运动进行EMG规范化方法的修订对于准确的生物力学分析至关重要.
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