Anti-Gravitational Growth-Associated Changes in the Mobilization of Leg Muscles during Walking in One Girl

摘要

Growth-related changes in the mobilization of leg muscles during walking were studied in human subject. Mobilization of soleus, lateral portion of gastrocnemius (LG)， and tibialis anterior (TA) muscles during the first walking steps in the life of a 12-month and11-day old baby girl was checked by recording electromyogram (EMG). The same recordings were also performed, when she became 15 years old. The body balance during walking was also monitored by recording the ground reaction forces on a three-dimensional force plate. Co-contraction of ankle plantar-flexors (soleus and LG) and dorsi-flexor (TA) was observed during the first walking in her life. The EMG amplitudes and the step intervals were not constant.