Abstract
[Purpose] The purpose of this study was to clarify the quantity of body burden during gait in the third trimester. [Subjects] Subjects were eight pregnant women in the third trimester and eight non-pregnant women; all were normally healthy and aged in their twenties and thirties. [Methods] A three-dimensional motion analysis system and a forceplate were used to determine gait speed, lower limbs and trunk angles, lower limbs and trunk joint moments, and floor reaction force. [Results] In pregnant women, the gait speed decreased, while the step width and the trunk extension angle increased. The hip joint flexion and abduction moment, the ankle joint plantar-flexion moment, and the trunk flexion moment increased with increase of the floor reaction force. [Conclusion] In the third trimester, the step width and the trunk extension angle increase due to body mass and center of gravity shift to a lower, anterior position. These results suggest that the burden on the abductor muscle, the ankle plantar-flexion muscles, the soft tissue of the anterior hip, and the rectus abdominis muscle increase.
