Department of Movement Neuroscience, Faculty of Sports Science, Leipzig University, Leipzig, Germany.
Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Scand J Med Sci Sports. 2022 Nov;32(11):1569-1580. doi: 10.1111/sms.14230. Epub 2022 Sep 16.
The interplay between biarticular and monoarticular muscles of the knee and hip joints during bipedal squats (SQ ) requires adequate central-nervous control mechanisms to enable smooth and dynamic movements. Here, we investigated motor control between M. vastus medialis (VM), M. vastus lateralis (VL), and M. rectus femoris (RF) in 12 healthy male recreational athletes during SQ with three load levels (50%, 62.5%, and 75% of 3-repetition maximum) following a standardized strength training protocol (3 sets of 10 repetitions). To quantify differences in motor control mechanisms in both time and frequency domains, we analyzed (1) muscle covariation via correlation analyses, as well as (2) common neural input via intermuscular coherence (IMC) between RF, VM, and VL. Our results revealed significantly higher gamma IMC between VM-VL compared with RF-VL and RF-VM for both legs. Correlation analyses demonstrated significantly higher correlation coefficients during ascent periods compared with descent periods across all analyzed muscle pairs. However, no load-dependent modulation of motor control could be observed. Our study provides novel evidence that motor control during SQ is characterized by differences in common input between biarticular and monoarticular muscles. Additionally, muscle activation patterns show higher similarity during ascent compared with descent periods. Future research should aim to validate and extend our observations as insights into the underlying control mechanisms offer the possibility for practical implications to optimize training concepts in elite sports and rehabilitation.
在双足深蹲（SQ）过程中，膝关节和髋关节的双关节肌和单关节肌之间的相互作用需要足够的中枢神经系统控制机制来实现平稳和动态的运动。在这里，我们研究了 12 名健康男性娱乐运动员在遵循标准化力量训练方案（3 组 10 次重复）后的 SQ 期间，M. vastus medialis (VM)、M. vastus lateralis (VL) 和 M. rectus femoris (RF) 之间的运动控制。为了在时间和频率域量化运动控制机制的差异，我们分析了 (1) 通过相关分析的肌肉协同作用，以及 (2) 通过 RF、VM 和 VL 之间的肌间相干性 (IMC) 的共同神经输入。我们的结果表明，在双足深蹲过程中，VM-VL 之间的伽马 IMC 明显高于 RF-VL 和 RF-VM，且两腿均如此。相关分析表明，与下降期相比，在上升期，所有分析的肌肉对之间的相关系数均显著更高。然而，没有观察到与运动控制相关的负载依赖性调制。我们的研究提供了新的证据，表明 SQ 期间的运动控制的特征是双关节肌和单关节肌之间的共同输入存在差异。此外，与下降期相比，上升期的肌肉激活模式具有更高的相似性。未来的研究应旨在验证和扩展我们的观察结果，因为对潜在控制机制的深入了解为优化精英运动和康复训练概念提供了可能。
