Akasaka Kiyokazu, Onishi Hideaki, Ihashi Kouji, Ichie Masayoshi, Handa Yasunobu
Department of Physical Therapy, Saitama Medical School Junior College, Saitama 350-0495, Japan.
Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-0932, Japan.
J Jpn Phys Ther Assoc. 2004;7(1):15-22. doi: 10.1298/jjpta.7.15.
Even though many investigators have analyzed the functional difference of the three heads of triceps surae in human, none of them succeeded to clarify the distinctive functional difference of those three muscles. The aim of this study was to investigate whether the integrated EMGs (IEMGs) of the triceps surae muscle, gastrocnemius and soleus, were task dependent. IEMGs of the medial head of the gastrocnemius (GM), lateral head of the gastrocnemius (GL), and soleus (SO) were investigated at three different knee joint angles, at four different duration of ramp contraction, with the generation of a single ongoing force, from 0 to the maximum voluntary contraction (MVC). Three-way ANOVAs for repeated measures were used to estimate differences in IEMG values in each of the GM, GL, and SO, taken at four different durations of ramp contraction (5, 10, 15 and 20 s), at three different knee joint angles (0 deg, 30 deg and 90 deg), across ankle plantar flexion levels of force (10, 20, 30, 40, 50, 60 and 70% MVC). According to three-way ANOVAs for repeated measures, IEMG of the GM muscle showed a first-order interaction between force and knee joint angle. In addition, IEMG of the GL muscle showed first-order interactions between the level of force and knee joint angle, and between the level of force and duration of ramp contraction. Furthermore, IEMG of the SO showed a main effect only on level of force. These results suggest that the each head of the triceps surae may work task dependently.
尽管许多研究人员分析了人类小腿三头肌三个头的功能差异，但他们都未能阐明这三块肌肉独特的功能差异。本研究的目的是调查小腿三头肌（腓肠肌和比目鱼肌）的积分肌电图（IEMG）是否依赖于任务。在三个不同的膝关节角度、四个不同的斜坡收缩持续时间下，在产生从0到最大自主收缩（MVC）的单一持续力的情况下，研究了腓肠肌内侧头（GM）、腓肠肌外侧头（GL）和比目鱼肌（SO）的IEMG。采用重复测量的三因素方差分析来估计在四个不同的斜坡收缩持续时间（5、10、15和20秒）、三个不同的膝关节角度（0度、30度和90度）、跨越踝关节跖屈力水平（10、20、30、40、50、60和70%MVC）时，GM、GL和SO各自IEMG值的差异。根据重复测量的三因素方差分析，GM肌的IEMG显示出力与膝关节角度之间的一级相互作用。此外，GL肌的IEMG显示出力水平与膝关节角度之间以及力水平与斜坡收缩持续时间之间的一级相互作用。此外，SO的IEMG仅显示出力水平的主效应。这些结果表明，小腿三头肌的每个头可能根据任务不同而发挥作用。
