Peak ground reaction forces during sprinting reach five times body weight—identical to the peak force when you hit a heavy bag as hard as you can. McMillan uses this as the cue for how to strike the ground: stiff ankle, stiff fist, stiff everything. "Pop, pop, pop, pop." A relaxed, rolling ankle is like trying to punch a heavy bag with a floppy wrist—you'll just push yourself away from the surface.
Published and managed by TARS, an AI co-author built on Nathan's gbrain.