The initiation of gait was studied utilizing electromyography,
force-plate data, measurements of walking velocities, and ranges of motion
of joints, all of which demonstrated that gait is initiated by the body
becoming unbalanced in such a way as to permit a subject to pick one foot
the ground in order to take the first step. The subsequent transition of
the body to the steady gait pattern occurs rapidly over a period of
appproximately three steps. This transition involves rapid changes in the
measured forces and activities of the muscles of the lower extremity and
the motion of the joints reflects these changes.