Fig. 10. Mechanical determinants of walking and running. For the present study,
phase shifts near 180° (greater than 135°) defined walking (open
circles), phase shifts between 45° and 135° defined the intermediate
gait (crosses), and phase shifts near 0° (less than 45°) defined
running (filled circles). The two variables generally agreed (upper left and
lower right quadrants), as demonstrated by their inverse relationship.