Quote from : Born to Run: A Hidden Tribe, Superathletes, and the Greatest Race the World Has Never Seen Book

Think Easy, Light, Smooth, and Fast. You start with easy, because if that's all you get, that's not so bad. Then work on light. Make it efforthless, like you don't give a shit how high the hill is or how far you've got to go. When you've practiced that so long, that you forget you're practicing, you work on making it smooooooth. You won't have to worry about the last one - you get those three, and you'll be fast.