Figure 7. Foot velocity and horizontal hip velocity at impact as a function of projection angle for a male soccer player. Data for Participant 1. The player’s foot velocity paralleled the projection velocity of the ball (data from ). This player had a constant ball-foot velocity ratio of 1.48 ± 0.05 and the player’s run-up velocity (i.e., hip velocity) made only a small contribution to the projection velocity of the ball.