Kipp Kristof, Redden Josh, Sabick Michelle, Harris Chad
Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, MI, USA.
J Appl Biomech. 2012 Jul;28(3):271-8. doi: 10.1123/jab.28.3.271. Epub 2011 Oct 4.
The purpose of this study was to identify multijoint lower extremity kinematic and kinetic synergies in weightlifting and compare these synergies between joints and across different external loads. Subjects completed sets of the clean exercise at loads equal to 65, 75, and 85% of their estimated 1-RM. Functional data analysis was used to extract principal component functions (PCF's) for hip, knee, and ankle joint angles and moments of force during the pull phase of the clean at all loads. The PCF scores were then compared between joints and across loads to determine how much of each PCF was present at each joint and how it differed across loads. The analyses extracted two kinematic and four kinetic PCF's. The statistical comparisons indicated that all kinematic and two of the four kinetic PCF's did not differ across load, but scaled according to joint function. The PCF's captured a set of joint- and load-specific synergies that quantified biomechanical function of the lower extremity during Olympic weightlifting and revealed important technical characteristics that should be considered in sports training and future research.
本研究的目的是确定举重过程中多关节下肢的运动学和动力学协同作用，并比较不同关节以及不同外部负荷下的这些协同作用。受试者以相当于其估计的1次最大重复量（1-RM）的65%、75%和85%的负荷完成抓举练习组。在所有负荷下抓举的上拉阶段，使用功能数据分析来提取髋、膝和踝关节角度以及力的主成分函数（PCF）。然后比较不同关节以及不同负荷下的PCF分数，以确定每个关节处每个PCF的占比情况以及不同负荷下的差异。分析提取了两个运动学PCF和四个动力学PCF。统计比较表明，所有运动学PCF以及四个动力学PCF中的两个在不同负荷下没有差异，但根据关节功能进行缩放。这些PCF捕捉到了一组特定于关节和负荷的协同作用，量化了奥运会举重过程中下肢的生物力学功能，并揭示了运动训练和未来研究中应考虑的重要技术特征。
