通过将推离力向量与质量轨迹中心对齐,可以提高转性能吗?
Paul Koster1, Sander Schreven1, Sina David2
1InnoSportLab de Tongelreep, Eindhoven, the Netherlands.
Journal of biomechanics
|April 19, 2025
概括
有效地将力转移到质量中心 (COM),而不是精确的对齐,显著提高了自由式翻转性能. 这一发现突出了优化墙面游泳速度的关键因素.
科学领域:
- 生物力学 生物力学
- 运动科学 运动科学 运动科学
- 流体动力学 流体动力学
背景情况:
- 自由式翻身转对于竞争性游泳表现至关重要.
- 以前的研究集中在峰值力和拉力指数上,忽视了力方向和身体对齐.
- 力量向量与质量中心 (COM) 轨迹对齐在转向性能中的作用尚不清楚.
研究的目的:
- 调查出口速度 (v_out) 和翻转性能取决于推离力向量与COM轨迹之间的对齐的假设.
- 为了确定精确的对齐或高效的力转移是否更为关键,以优化转向性能.
主要方法:
- 收集了七名训练有素的游泳者在最大努力下翻转时的高速同步视频和力数据 (F_peak).
- 计算了COM-力向量对齐,并将其与v_out和力成分相关联.
- 分析了平均角度差异和力向量的投射到COM向量上.
主要成果:
- 在v_out和力向量和COM轨迹之间的平均角度差异之间没有发现显著的相关性.
- 在v_out和力向量投射到COM向量之间观察到强烈的相关性 (r=0.76,p<0.001).
- 在v_out和峰值水平和垂直力之间发现了中等的相关性.
结论:
- 对COM的有效力转移,而不是精确的向量对齐,是转性能的主要决定因素.
- 游泳表现可能更受益于在推开过程中有效的力转移.
- 需要进一步的研究来阐明垂直力和相位特定的壁接触力学在游泳推力的作用.
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