Fig. 4. Schematic of sagittal plane parameters for the forelimbs (above) and hindlimbs (below) of M. domestica on level, incline and decline trackways (left to right). Fore- and hindlimb touchdown (solid gray bar) and lift-off (open bar) angles are exaggerated to make differences between limbs and substrates more visible. Vertical impulse is represented by broken arrows, and braking and propulsive impulses by solid arrows; the magnitudes of these impulse vectors are also not shown to scale with each other for illustrative effect (see Table 1 for exact values). B, braking impulse; P, propulsive impulse.