human urine is both nutrient-rich and an effective tooth whitener

That was the real secret of the Tarahumara: they'd never forgotten what it felt like to love running. They remembered that running was mankind's first fine art, our original act of inspired creation.

Endurance, after all, is the only reason we even exist. We think of ourselves as nature's deadliest animals, but the truth is, a naked human is the biggest wimp in the wild. We have no fangs, no claws, no strength, and no speed.

Make friends with pain, and you will never be alone.~Ken Chlouber, Colorado miner and creator of the Leadville Trail 100 mile race

In 'Tarahumara' land, there was no crime, war or theft. There was no corruption, obesity, drug addiction, greed, wife-beating, child abuse, heart disease, high blood pressure, or carbon emissions. They didn't get diabetes, or depressed, or even old: 50-year-olds outran teenagers.

Faced with the almost inescapable conclusion that it had been selling lemons, Nike shifted into make-lemonade mode. Jeff Pisciotta became head of a top-secret and seemingly impossible project: finding a way to make a buck off a naked foot.

Only recently have we come up with the technology to turn lazing around into a way of life. We've taken our sinewy, durable, hunter-gatherer bodies and plunked them into an artificial world of leisure.