Powell Douglas W, Paquette Max R, Williams D S Blaise
1School of Health Studies, University of Memphis, Memphis, TN; 2Department of Physical Therapy, Virginia Commonwealth University, Richmond, VA; and 3Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA.
Med Sci Sports Exerc. 2017 Aug;49(8):1662-1667. doi: 10.1249/MSS.0000000000001279.
High-arched (HA) athletes exhibit greater lower extremity stiffness during functional tasks than low-arched (LA) athletes. The contributions of skeletal and muscular structures to stiffness may underlie the distinct injury patterns observed in these athletes. The purpose of this study was to compare skeletal and muscular contributions to leg stiffness in HA and LA athletes during running and landing tasks.
Ten HA and 10 LA female athletes performed five overground running trials at a self-selected pace and five step off bilateral landing trials from a height of 30 cm. Three-dimensional kinematics and kinetics were collected using a motion capture system and a force platform. Leg stiffness and its skeletal and muscular contributions were calculated. Independent t-tests were used to compare variable means between arch type groups and Cohen's d were computed to assess effect sizes of mean differences.
In running, HA athletes had greater leg stiffness (P = 0.010, d = 1.03) and skeletal stiffness (P = 0.016, d = 0.81), although there are no differences in muscular stiffness (P = 0.134). During landing, HA had greater leg stiffness (P = 0.015, d = 1.06) and skeletal stiffness (P < 0.001, d = 1.84), whereas LA athletes had greater muscular stiffness (P = 0.025, d = 0.96).
These findings demonstrate that HA athletes place a greater reliance on skeletal structures for load attenuation during running and landing, whereas LA athletes rely more greatly on muscle contributions during landing only. These findings may provide insight into the distinct injury patterns observed in HA and LA athletes.
高足弓（HA）运动员在功能性任务中表现出比低足弓（LA）运动员更大的下肢刚度。骨骼和肌肉结构对刚度的贡献可能是这些运动员中观察到的不同损伤模式的基础。本研究的目的是比较HA和LA运动员在跑步和着陆任务中骨骼和肌肉对腿部刚度的贡献。
10名HA和10名LA女性运动员以自我选择的速度进行5次地面跑步试验，并从30厘米的高度进行5次双侧着陆试验。使用运动捕捉系统和测力平台收集三维运动学和动力学数据。计算腿部刚度及其骨骼和肌肉贡献。使用独立样本t检验比较足弓类型组之间的变量均值，并计算科恩d值以评估均值差异的效应大小。
在跑步时，HA运动员的腿部刚度（P = 0.010，d = 1.03）和骨骼刚度（P = 0.016，d = 0.81）更大，尽管肌肉刚度没有差异（P = 0.134）。在着陆过程中，HA的腿部刚度（P = 0.015，d = 1.06）和骨骼刚度（P < 0.001，d = 1.84）更大，而LA运动员的肌肉刚度更大（P = 0.025，d = 0.96）。
这些发现表明，HA运动员在跑步和着陆过程中更依赖骨骼结构来减轻负荷，而LA运动员仅在着陆过程中更依赖肌肉贡献。这些发现可能有助于深入了解HA和LA运动员中观察到的不同损伤模式。
