NSCA Sprinting and Running Practice Test

In sprint mechanics, the push-off angle during the rear-support phase reflects the direction of the propulsive impulse as the foot leaves the ground. Sprinters typically drive off with an angle around the mid-50s degrees relative to the surface. This range provides a strong forward (horizontal) component to speed up the body, while still supplying enough vertical lift to keep the flight phases efficient and the swing leg moving forward.

If the angle were much smaller (like 30–35 degrees), the push would be too horizontal, limiting vertical lift and potentially reducing the ability to clear the leg efficiently. If the angle were much larger (60–65 degrees), the push would be too steep, increasing vertical impulse and wasting forward momentum. An angle around 40–45 degrees sits between these extremes but is typically a bit lower than what's commonly observed in top sprinters.

Thus, the typical push-off angle in the rear support phase is about 50–55 degrees, balancing forward propulsion with adequate vertical lift.