Three-dimensional motion of the center of gravity of the body during walking

A kinematic gait analysis system was used to determine the 3-D motion of the center of the pelvis during walking, in 10 normal adults of both sexes. At the same time, force platform data were integrated twice to determine the 3-D motion of the center of gravity of the body. In general, the center of the pelvis showed greater excursions than the center of gravity of the body, so that within the pelvis, the center of gravity moved in the opposite direction to the motion of the trunk. In the medio-lateral and vertical directions, the phasing of motion was very similar between the center of gravity and the center of the pelvis. In the direction of progression, the motion of the center of the trunk led that of the center of gravity of the body with a phase difference of about 5 degrees. Although the motion of the center of gravity within the pelvis during gait clearly relates to movements of the arms, legs and trunk, further studies would be needed to examine this motion in detail.