Santos Paulo D G, Vaz João R, Correia Paulo F, Valamatos Maria J, Veloso António P, Pezarat-Correia Pedro
Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1495-751 Cruz Quebrada, Portugal.
CIPER, Faculty of Human Kinetics, Lisbon University, 1495-751 Cruz Quebrada, Portugal.
J Funct Morphol Kinesiol. 2020 Oct 22;5(4):75. doi: 10.3390/jfmk5040075.
Muscle synergy extraction has been utilized to investigate muscle coordination in human movement, namely in sports. The reliability of the method has been proposed, although it has not been assessed previously during a complex sportive task. Therefore, the aim of the study was to evaluate intra- and inter-day reliability of a strength training complex task, the power clean, assessing participants' variability in the task across sets and days. Twelve unexperienced participants performed four sets of power cleans in two test days after strength tests, and muscle synergies were extracted from electromyography (EMG) data of 16 muscles. Three muscle synergies accounted for almost 90% of variance accounted for (VAF) across sets and days. Intra-day VAF, muscle synergy vectors, synergy activation coefficients and individual EMG profiles showed high similarity values. Inter-day muscle synergy vectors had moderate similarity, while the variables regarding temporal activation were still strongly related. The present findings revealed that the muscle synergies extracted during the power clean remained stable across sets and days in unexperienced participants. Thus, the mathematical procedure for the extraction of muscle synergies through nonnegative matrix factorization (NMF) may be considered a reliable method to study muscle coordination adaptations from muscle strength programs.
肌肉协同作用提取已被用于研究人类运动（即体育运动）中的肌肉协调。该方法的可靠性已被提出，尽管此前尚未在复杂的体育任务中进行评估。因此，本研究的目的是评估一项力量训练复杂任务——高翻的日内和日间可靠性，评估参与者在该任务中每组及不同日期之间的变异性。12名无经验的参与者在力量测试后的两个测试日中进行了四组高翻动作，并从16块肌肉的肌电图（EMG）数据中提取肌肉协同作用。三组肌肉协同作用几乎占了每组及不同日期之间解释方差（VAF）的90%。日内VAF、肌肉协同作用向量、协同作用激活系数和个体肌电图图谱显示出高相似性值。日间肌肉协同作用向量具有中等相似性，而关于时间激活的变量仍有很强的相关性。目前的研究结果表明，在无经验的参与者中，高翻过程中提取的肌肉协同作用在每组及不同日期之间保持稳定。因此，通过非负矩阵分解（NMF）提取肌肉协同作用的数学程序可被认为是一种可靠的方法，用于研究肌肉力量训练计划中的肌肉协调适应性。
