Fig. 9. Exaggerated walking gait. Angular momentum, horizontal ground reaction force and ground reference points are plotted in the medio-lateral (x) and anterior–posterior (y) directions. In this experiment a participant walked with exaggerated leg protraction and retraction movements, similar to a military marching gait, at a forward speed of 1.3 m s^–1 (see whole-body sketches above plots). (A,B) The horizontal components of normalized angular momentum are plotted versus percentage gait cycle. For ease of comparison with walking values shown in Fig. 3A, the angular momentum is normalized by the product of the participant's mass, CM height, and self-selected gait speed (MVH; see participant no. 1 in Table 1). Here 0% and 100% gait cycles correspond to consecutive heel strikes of the same foot. (C,D) The horizontal ground reaction forces measured experimentally (thin blue line) are plotted along with the calculated zero-moment forces (thick red line) versus percentage gait cycle for the same participant and trial as in A and B. Here 0% to 50% gait cycle spans from the middle of a single-support phase to the middle of the next single-support phase of the opposite limb. (E) Plotted are the CP (blue dashed line), CMP (red solid line) and CM ground projection (green dash-dotted line) trajectories and corresponding footprints. As in C and D, only 50% of the gait cycle is shown. The two circles on each line denote the transition from single to double support, and vice versa. For this exaggerated gait, the CMP often falls outside the ground support envelope.