Do you run every day? Do you feel pain when you run? In fact, humans are born to run with extremely springy legs and dense sweat glands, which allow us to run and cool off simultaneously. The greatest distance runners on earth are the reclusive Tarahumara, who live in the Copper Canyons of Mexico. They chase prey in the mountain and can run for dozens of hours without getting injured. This book unveils the mysteries of the Tarahumara and their secrets about running.