Most people think sprinting fast is just about force. It’s not. At...
Fred Duncan@Fred__Duncan
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Jul 18, 2025
~1 min read
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Most people think sprinting fast is just about force. It’s not.
At max velocity, ground contact times are under 0.12 seconds, you don’t have time to impart max force, you have to apply it instantly. That’s where stiffness and jerk come in.
At max velocity, ground contact times are under 0.12 seconds, you don’t have time to impart max force, you have to apply it instantly. That’s where stiffness and jerk come in.
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Jerk = the rate of change of acceleration.
It’s not just about producing force, but how fast you produce it.
High stiffness + high jerk = high output in a small impulse window.
fredduncantraining.com/product/the-co…
It’s not just about producing force, but how fast you produce it.
High stiffness + high jerk = high output in a small impulse window.
fredduncantraining.com/product/the-co…