Movie 1

Three walking sequences at Uʹ = 0:3 show how four-beat walking does not look qual itatively different as Î increases. However, the forces of the vaulting limb during transfer of support of the opposite pair do change systematically (Fig 2B-D). Animations are adjusted so that one stride cycle takes 4 seconds. Leg transparency is proportional to ground reaction force, as a fraction of maximal force. Leg contact is displayed when ground reaction force exceeds 0:01mg. The center of mass (COM) is marked with an “x”, while squares mark a radius of gyration from the COM.