The support phase duration in sprinting maximum velocity is within which range, and the maximum Newton ground reaction force is up to how many Newtons?

The support phase duration in sprinting maximum velocity is within which range, and the maximum Newton ground reaction force is up to how many Newtons?

• A. 0.06 to 0.08 seconds, 1600
• B. 0.08 to 0.10 seconds, 1800
• C. 0.10 to 0.12 seconds, 2000
• D. 0.05 to 0.07 seconds, 1500

Answer: (B)

During maximal velocity sprinting, the foot stays on the ground for about 0.08–0.10 seconds with each step. This contact time balances the need to generate propulsive force with the desire to increase step rate, allowing the sprinter to maintain top speed rather than slowing down. The ground reaction force at that moment is very high, typically peaking around 1800 Newtons, because the body requires a strong push off the ground in a very short time to sustain velocity. Even though the contact is brief, the force is large enough to provide the necessary impulse for forward propulsion and vertical support. So the combination of a roughly 0.08–0.10 second stance and a peak near 1800 N best matches what happens at max velocity. Shorter contact times or higher/lower force values would correspond to different sprint phases or different mechanics and aren’t as representative of maximal velocity sprinting.

During maximal velocity sprinting, the foot stays on the ground for about 0.08–0.10 seconds with each step. This contact time balances the need to generate propulsive force with the desire to increase step rate, allowing the sprinter to maintain top speed rather than slowing down. The ground reaction force at that moment is very high, typically peaking around 1800 Newtons, because the body requires a strong push off the ground in a very short time to sustain velocity. Even though the contact is brief, the force is large enough to provide the necessary impulse for forward propulsion and vertical support. So the combination of a roughly 0.08–0.10 second stance and a peak near 1800 N best matches what happens at max velocity. Shorter contact times or higher/lower force values would correspond to different sprint phases or different mechanics and aren’t as representative of maximal velocity sprinting.