Legreneur P, Morlon B, Van Hoecke J
Groupe Analyse du Mouvement, UFR-STAPS, Université de Bourgogne, Dijon, France.
C R Seances Soc Biol Fil. 1996;190(5-6):621-32.
The main purpose of this study was to investigate the maximal isometric plantarflexion moment as a function of the triceps surae's length. As the gastrocnemius are bi-articular actuators, their respective lengths were modified by variations of the ankle and knee joints angles. The mechanical results agreed ones previously published in the literature. The maximal and minimal isometric moments were attained at maximal lengthening and shortening of the gastrocnemius respectively. The gastrocnemius electromyographic (EMG) activities showed paradoxal results. Their EMG activities decreased with their lengthening when this was induced by ankle joint angle variations. Inversely, their EMG activities increased with their lengthening when this was induced by knee joint angle variations. These results allowed the authors to hypothesize the existence of specific recruitment of neuro-muscular compartments of the gastrocnemius with knee extension.
本研究的主要目的是探讨最大等长跖屈力矩作为小腿三头肌长度的函数。由于腓肠肌是双关节驱动肌，其各自的长度通过踝关节和膝关节角度的变化而改变。力学结果与先前文献中发表的结果一致。最大和最小等长力矩分别在腓肠肌最大拉长和缩短时获得。腓肠肌肌电图（EMG）活动显示出矛盾的结果。当由踝关节角度变化引起腓肠肌拉长时，其EMG活动随拉长而降低。相反，当由膝关节角度变化引起腓肠肌拉长时，其EMG活动随拉长而增加。这些结果使作者能够推测随着膝关节伸展，腓肠肌神经肌肉节段存在特定的募集情况。
