疲劳任务期间腿筋活跃度的变化是由收缩时间而不是强度调节的
Antonio Martínez-Serrano1,2,3, Régis Radaelli4, Tomás T Freitas1,2,3,5
1UCAM Research Center for High Performance Sport, UCAM Universidad Católica de Murcia, Murcia, Spain.
Scientific reports
|October 22, 2024
概括
疲劳期间的腿筋活跃度变化更多地取决于肌肉收缩的时间,而不是强度. 较低强度 (20% MVIC) 的疲劳导致半体的显著刚性变化,而不是较高强度 (40% MVIC) 的疲劳.
科学领域:
- 生物力学 生物力学
- 肌肉骨生理学 肌肉骨生理学
- 运动科学 运动科学 运动科学
背景情况:
- 超声波剪切波弹性学越来越多地用于研究腿筋硬.
- 在不同收缩强度的疲劳期间,关于两腿长头 (BFlh) 和半 (ST) 肌肉在疲劳时的活跃度的研究有限.
研究的目的:
- 为了比较膝关节曲器同位数收缩对疲劳的影响,在20%的最大自发同位数收缩 (MVIC) 与40%的最大自发同位数收缩 (MVIC) 对BFlh和ST肌肉的活跃度的影响.
主要方法:
- 18名娱乐活跃的男性参加了两次实验性会议.
- 参与者在20%或40%的MVIC时进行了对称膝盖 flexor收缩,以致于疲劳.
- 使用剪切波弹性学测量了BFlh和ST的活跃肌肉性.
主要成果:
- 在20%的MVIC下,BFlh活性度没有变化,而ST活性度显著下降. 在40%的MVIC下,无论是BFlh还是ST都没有显示出显著的肌肉内硬度变化.
- 肌肉间活性度差异在20%的MVIC (64%的收缩时间) 与40%的MVIC (33%的收缩时间) 相比,持续时间更长.
- 在20%的MVIC疲劳任务中,BFlh/ST硬度比率在40%的MVIC任务中增加得更快.
结论:
- 收缩的持续时间似乎是一个比收缩强度更关键的因素,在疲劳时改变腿筋机械性质.
- 这些发现有助于了解肌肉疲劳机制,并可能为腿筋损伤的训练和康复策略提供信息.
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