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数据规范化在棒球投球中的使用和可接受性
Kevin A Giordano1, Adam J Barrack2, William M Murrah3
1Departments of Orthopedics and Physical Therapy, Holy Cross Orthopedics Institute, Fort Lauderdale, FL, USA.
Sports biomechanics
|January 12, 2024
概括
棒球投球中的比率正常化生物力学并不能完全解释运动员尺寸差异. 这影响了投篮速度如何预测肘部扭矩,影响了伤害风险分析.
科学领域:
- 体育 生物力学 运动 生物力学
- 棒球投球分析 棒球投球分析
- 伤害预防 研究 研究 研究 预防伤害
背景情况:
- 棒球投球中的动力值通常以质量或质量*高度进行正常化,以进行运动员之间的比较.
- 规范化方法必须满足统计假设,以确保准确的数据解释.
- 之前的研究还没有完全评估正常化对投篮生物力学中预测关系的影响.
研究的目的:
- 为了调查肘扭矩的正常化是否会影响投球速度的预测.
- 为了比较回归模型与没有规范的扭矩值,以评估规范化的影响.
- 为了确定常见的规范化技术是否足够考虑中的人体测量变化.
主要方法:
- 从1988年青年到职业棒球投手的运动捕捉数据的回顾性分析.
- 通过比较带零截点和没有零截点的线性回归模型来测试规范化假设.
- 检查混的人类测量变量和规范扭矩之间的剩余相关性.
- 使用回归模型比较来评估速度对扭矩的预测效应.
主要成果:
- 质量和质量*高度的正常化并没有消除与肘扭矩的关系.
- 投速度预测只有10%的异常在非正常的肘部扭矩.
- 正常化的扭矩显示出更高的方差预测:质量正常化的扭矩为59%,质量*高度正常化的扭矩为45%.
- 正常化导致了关于速度对扭矩影响的大小的不同结论.
结论:
- 棒球投球生物力学中的比率正常化并不能完全解释个体的人类测量差异.
- 正常化可以改变投球速度和肘部扭矩之间的感知关系.
- 建议对回归模型进行比较,以适当考虑投球运动数据分析中的人类学变量.
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