How do athletes run so fast?

Elite sprinters run so fast because they push the track very hard, very quickly, and their bodies turn that push into forward motion. Powerful legs, springy fast-twitch muscle, quick steps, strong arm swings, and a forward lean all work together for a few blazing seconds.

One delightful detail is how little time each foot gets. At full speed, a world-class sprinter may touch the ground more than four times every second, landing with huge force and leaving again almost instantly, as if the track were a trampoline they trained for years to use.