Sonographic Observation of the Dynamics of the Lateral Abdominal Region Muscles during Walking

Abstract

[Purpose] Sonography was used to observe the dynamics of the lateral abdominal region muscles during walking. [Subjects] The lateral abdominal region muscles of the 30 male healthy volunteers who participated in this study. [Methods] The linear probe (12 MHz) of the sonograph was positioned over the lateral abdominal region muscle so that the rectus abdominis at the umbilical level, the muscle bellies of the external and internal oblique muscles, and the transversus abdominis could be seen. Walking was recorded in the sagittal plane using a digital video camera which was synchronized with the sonograph. The thickness and deviation of the anterior border of the four lateral abdominal region muscles during walking were calculated. [Results] All of the muscles moved ventrally from mid stance to terminal stance, and they moved dorsally during the swing phase. The thickness ratio of the transversus abdominis was significantly greater than that of the external oblique muscle. [Conclusion] It is possible to conduct stabilization training for the trunk during walking, since the lateral abdominal muscles show small thickness changes and deviations, the internal oblique muscle has higher activity, and the muscle contract-relax of the transversus abdominis is clearly evident.