在骑自行车时肌肉疲劳,踩踏技巧和缓慢组件
Keenan B MacDougall1, Saied J Aboodarda1, Paulina H Westergard1
1Faculty of Kinesiology, University of Calgary, Calgary, Canada.
Experimental physiology
|October 16, 2024
概括
氧气吸收的缓慢成分 (V·O2缓慢) 与骑自行车时的肌肉疲劳有关,但踩踏技术也可能影响它. 个体反应有很大的差异,这表明叠加效应.
科学领域:
- 运动生理学 运动生理学
- 运动科学 运动科学 运动科学
- 生物力学 生物力学
背景情况:
- 氧气吸收的缓慢成分 (V·O2缓慢) 出现在第一个乳酸值以上,可能与肌肉疲劳有关.
- 在疲劳的骑自行车运动中,踩踏技巧调整在V·O2缓慢中的作用仍然不清楚.
- 现有证据表明肌肉疲劳和VO2缓慢之间的因果关系是模两可的.
研究的目的:
- 为了研究肌肉疲劳,心肺呼吸反应和疲劳骑自行车时的踏板技术之间的关系.
- 探索踏板技术调整在持续高强度骑行过程中对V·O2缓慢的贡献.
主要方法:
- 11名参与者完成了超过第二个乳酸值的恒定功率循环试验.
- 通过大腿神经刺激评估肌肉疲劳;记录了心肺呼吸测量 (V̇O2),四头骨氧化,EMG和踏板力.
- 在团体和个人层面分析了生理和机械变量之间的相关性.
主要成果:
- 在V̇O2缓慢和四头肌抽力 (r = -0.51) 和肌肉氧化 (r = -0.52) 之间发现了中等相关性.
- 观察到V̇O2慢和EMG振幅/频率,以及踩踏机械变量之间存在弱相关性.
- 在相关性中显著的个体间变异性表明对疲劳性运动的异质反应.
结论:
- 这些发现与文献相一致,该文献将肌肉疲劳大小与V·O2缓慢大小联系起来,但具有相当大的个体差异.
- 这项研究表明,踩踏技术的调整可能会"叠加"V·O2缓慢的增加到与疲劳相关的潜在变化.
- 由于数据异质性,确定踏板技术对V̇O2slow的精确影响具有挑战性.
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