增加负载承载能力和运行速度对肌肉力量的大小,变化和协调模式有不同的影响
Coline Van Waerbeke1, Richard W Willy2, André Jacques1
1Aix Marseille Univ, CNRS, ISM, Marseille, France.
Journal of biomechanics
|September 10, 2023
概括
加重负荷的跑步增加了肌肉力量的幅度和变化,而更高的速度减少了变化. 个体肌肉协调模式保持一致,但稍微适应负载和速度的变化.
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:
- 了解跑步机械在不同负载和速度下如何变化,对于性能和伤害预防至关重要.
- 肌肉力量特征和协调模式是运行经济和受伤风险的关键决定因素.
研究的目的:
- 研究不同跑步速度和外部负荷对肌肉力量幅度,变异性和协调模式的影响.
- 区分个体间和个体内对改变运行条件的反应.
主要方法:
- 9名健康的参与者在各种条件下 (两个速度,三个负载) 在仪器化跑步机上跑步.
- 动力学和动力学被记录下来,用肌肉骨模型估计下肢肌肉力量.
- 统计参数映射和具有多维缩放的协差矩阵被用于组和个体分析.
主要成果:
- 增加跑步速度或负载显著增加肌肉力量幅度 (p < 0.01).
- 较高的负载增加了脚关节肌肉力变化 (高达体重5%; p < 0.05),而速度增加减少了变化 (高达体重10%; p < 0.05).
- 个体肌肉力量协调模式是不同的,并显示了轻微的适应速度和负载变化 (p <0.05).
结论:
- 外部负载增强增强了在跑步期间肌肉力量的幅度和变化.
- 增加跑步速度主要降低了肌肉力量的变化.
- 研究结果为军人和步道跑者提供了培训计划,并通过管理机械负荷来帮助设计受伤康复策略.
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