协同肌肉是如何相互作用的,当他们的收缩旨在稳定和微调运动时,哪些是由拮抗肌引起的?该研究的目的是与负重控制任务相比,在微调控制任务中分析二头肌和肱拉肌的相互作用。肱二头肌表面肌电图,在15名健康受试者中检查了不同收缩水平组合的动态屈伸运动中的肱和肱三头肌,关节角度和角速度。测量在两种配置中进行,其中,由于外部负载引起的扭矩与肘部弯曲(承载任务)或肘部伸展(微调任务)的旋转方向相反。而在承载控制任务期间,在所有关节角度观察到类似的肱二头肌和肱桡肌的肌肉激活,角速度和外部载荷,在微调控制任务中,在1kg时观察到两个屈肌的肌肉激活的显着差异,F(3.639,47.305)=2.864,p=0.037,外部载荷为5kg,F(1.570,21.976)=6.834,p=0.008。结果证实了在承重任务期间两个屈肌的协同肌肉激活,但是当两个屈肌包括微调控制任务时,建议对它们采取不同的控制策略。
How do synergistic muscles interact, when their contraction aims at stabilizing and fine-tuning a movement, which is induced by the antagonistic muscle? The aim of the study was to analyze the interaction of biceps and brachioradialis during fine-tuning control tasks in comparison to load bearing ones. The surface electromyogram of biceps, brachioradialis and triceps were examined in 15 healthy subjects in dynamic flexion and extension movements with different combinations of contraction levels, joint angles and angular velocities. The measurements were conducted in two configurations, where the torque due to an external load opposes the rotational direction of the elbow flexion (load bearing tasks) or the elbow extension (fine-tuning tasks). Whereas during load bearing control tasks, similar muscular activation of biceps and brachioradialis was observed for all joint angles, angular velocities and external loads, during fine-tuning control tasks a significant difference of the muscular activation of both flexors was observed for 1kg, F(3.639,47.305)=2.864, p=0.037, and 5kg of external load, F(1.570,21.976)=6.834, p=0.008. The results confirm the synergistic muscular activation of both flexors during load bearing tasks, but suggest different control strategies for both flexors when they comprise a fine-tuning control task.