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.

I received the best advice for running I ever heard: 'You're not going to win, so just relax. If it feels like work, you're running too hard.

But yeah, Ann [Trason] insisted, running was romantic; and no, of course her friends didn't get it because they'd never broken through. For them, running was a miserable two miles motivated solely by size 6 jeans: get on the scale, get depressed, get your headphones on, and get it over with. But you can't muscle through a five-hour run that way; you have to relax into it, like easing your body into a hot bath, until it no longer resists the shock and begins to enjoy it.

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.

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.

Every morning in Africa, a gazelle wakes up, it knows it must outrun the fastest lion or it will be killed. Every morning in Africa, a lion wakes up. It knows it must run faster than the slowest gazelle, or it will starve. It doesn't matter whether you're the lion or a gazelle-when the sun comes up, you'd better be running.

Running is the heart of what it means to be human.