We were born to run; we were born because we run.

Nearly all runners do their slow runs too fast, and their fast runs too slow." Ken Mierke says. "So they're just training their bodies to burn sugar, which is the last thing a distance runner wants. You've got enough fat stored to run to California, so the more you train your body to burn fat instead of sugar, the longer your limited sugar tank is going to last." -The way to activate your fat-burning furnace is by staying below your aerobic threshold--your hard-breathing point--during your endurance runs.

When it comes to mentors, you can't beat survival.

We say the rarajipari is the game of life, ' Angel said. 'You never know how hard it will be. You never know when it will end. You can't control it. You can only adjust.

He was onto something. Something huge. It wasn't just how to run; it was how to live, the essence of who we are as a species and what we're meant to be.

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.

Humans are built for endurance, not speed. We're awful sprinters compared to every other animal. We try to run our races as if they were speed races, but they are not. They're endurance races. Even a marathon, the way it's run now, it's not an endurance contest.