Faculty of Sport, University of Ljubljana, 1000 Ljubljana, Slovenia.
Faculty of Health Sciences, University of Primorska, 6310 Izola, Slovenia.
Int J Environ Res Public Health. 2021 Mar 19;18(6):3168. doi: 10.3390/ijerph18063168.
Muscle coordination is important for rational and effective planning of therapeutic and exercise interventions using equipment that mimics functional movements. Our study was the first to assess muscle coordination during flywheel (FW) squats.
Time-of-peak electromyographic activation order was assessed separately for 8, 4, and 3 leg muscles under four FW loads. A sequential rank agreement permutations tests (SRA) were conducted to assess activation order and Kendall's tau was used to assess the concordance of activation order across subjects, loads and expected order of activation.
SRA revealed a latent muscle activation order at loads 0.05, 0.075, and 0.1, but not at 0.025 kg·m. Kendall's tau showed moderate-to-strong concordance between the expected (proximal-to-distal) and the observed muscle activation order only at a load 0.025 kg·m, regardless of the number of muscles analyzed. Muscle activation order was highly concordant between loads 0.05, 0.075, and 0.1 kg·m.
The results show a specific role of each muscle during the FW squat that is load-dependent. While the lowest load follows the proximal-to-distal principle of muscle activation, higher loads lead to a reorganization of the underlying muscle coordination mechanisms. They require a specific and stable muscle coordination pattern that is not proximal-to-distal.
肌肉协调对于使用模拟功能性运动的设备进行理性和有效的治疗和运动干预的计划非常重要。我们的研究首次评估了飞轮（FW）深蹲过程中的肌肉协调。
在四个 FW 负荷下，分别评估了 8、4 和 3 个腿部肌肉的肌电激活峰值时间顺序。进行了顺序等级同意排列检验（SRA）以评估激活顺序，Kendall 的 tau 用于评估激活顺序在受试者、负荷和预期激活顺序之间的一致性。
SRA 显示在 0.05、0.075 和 0.1 kg·m 的负荷下存在潜在的肌肉激活顺序，但在 0.025 kg·m 的负荷下不存在。Kendall 的 tau 仅在 0.025 kg·m 的负荷下显示出预期（近-远）和观察到的肌肉激活顺序之间的中等至强一致性，无论分析的肌肉数量如何。在 0.05、0.075 和 0.1 kg·m 的负荷下，肌肉激活顺序高度一致。
结果表明，FW 深蹲过程中的每个肌肉都有特定的作用，这取决于负荷。虽然最低负荷遵循肌肉激活的近-远原则，但更高的负荷会导致潜在的肌肉协调机制重新组织。它们需要特定且稳定的肌肉协调模式，而不是近-远。
