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使用飞行时间方法估计跳跃高度的错误:模拟起飞和降落之间脚位置的影响
Carlos Gonçalves1, Roberto Baptista2, James Tufano3
1University of Brasília, Faculty of Physical Education, Brasília, Distrito Federal, Brazil.
PeerJ
|September 3, 2024
概括
使用飞行时间 (FT) 估计垂直跳跃高度可能由于姿势变化而不准确. 模拟显示,脚位置的变化可能导致严重的高估,高达60%.
科学领域:
- 生物力学 生物力学
- 人类运动分析 人类运动分析
- 运动科学 运动科学 运动科学
背景情况:
- 垂直跳跃高度通常使用飞行时间 (FT) 来估计.
- 在起飞和降落期间保持一致的身体姿势对于精确的基于FT的跳跃高度估计至关重要.
- 跳跃之间姿势的变化,特别是脚的位置,可以引入重大错误.
研究的目的:
- 使用FT模拟和量化由于从起飞到降落时脚位置的变化而导致的跳跃高度估计错误.
- 为了确定跨越不同个体身高和跳跃能力的跳跃高度潜在高估的范围.
- 提出一种方法来提高基于FT的跳跃高度测量的准确性.
主要方法:
- 计算机模拟被用来模拟垂直跳跃.
- 模拟包括质量中心的变化,脚的位置 (背部曲),受试者的身高 (1.44-1.98米) 和跳跃高度 (10-30厘米).
- 分析了在着陆期间不受控制的脚位置对FT衍生的跳跃高度的影响.
主要成果:
- 从FT估计跳跃高度,而不考虑脚位置,可能会导致过高估计.
- 过高估计可以达到18%的平均个体和高达60%的高个体执行低跳.
- 这些错误在增加负载的场景中或在比较具有不同跳跃技术的个体时尤为重要.
结论:
- 飞行时间是估计垂直跳跃高度的潜在有缺陷的方法,如果脚动力学没有控制.
- 提出了一个校正方程式,以减轻错误,并提高基于FT的跳跃高度测量的有效性.
- 实施这种纠正可以在垂直跳跃性能评估中进行更公平的学科间比较.
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