From an interview with Christopher McDougall on Amazon.com:
Question: Born to Run explores the life and running habits of the Tarahumara Indians of Mexico’s Copper Canyon, arguably the greatest distance runners in the world. What are some of the secrets you learned from them?
Christopher McDougall: The key secret hit me like a thunderbolt. It was so simple, yet such a jolt. It was this: everything I’d been taught about running was wrong. We treat running in the modern world the same way we treat childbirth—it’s going to hurt, and requires special exercises and equipment, and the best you can hope for is to get it over with quickly with minimal damage.
Then I meet the Tarahumara, and they’re having a blast. They remember what it’s like to love running, and it lets them blaze through the canyons like dolphins rocketing through waves. For them, running isn’t work. It isn’t a punishment for eating. It’s fine art, like it was for our ancestors. Way before we were scratching pictures on caves or beating rhythms on hollow trees, we were perfecting the art of combining our breath and mind and muscles into fluid self-propulsion over wild terrain. And when our ancestors finally did make their first cave paintings, what were the first designs? A downward slash, lightning bolts through the bottom and middle—behold, the Running Man.
The Tarahumara have a saying: “Children run before they can walk.” Watch any four-year-old—they do everything at full speed, and it’s all about fun. That’s the most important thing I picked up from my time in the Copper Canyons, the understanding that running can be fast and fun and spontaneous, and when it is, you feel like you can go forever. But all of that begins with your feet. Strange as it sounds, the Tarahumara taught me to change my relationship with the ground. Instead of hammering down on my heels, the way I’d been taught all my life, I learned to run lightly and gently on the balls of my feet. The day I mastered it was the last day I was ever injured. (http://www.amazon.com/Born-Run-Hidden-Superathletes-Greatest/dp/0307266303)
Today. I finished Week 2. I concentrated solely on running lightly and gently on the balls of my feet. It wasn’t even close to fine art, but it was really nice.