In this controversial and engaging exploration of athletic success and the so-called 10,000-hour rule, David Epstein tackles the great nature vs. nurture debate and traces how far science has come in solving it. Through on-the-ground reporting from below the equator and above the Arctic Circle, revealing conversations with leading scientists and Olympic champions, and interviews with athletes who have rare genetic mutations or physical traits, Epstein forces us to rethink the very nature of athleticism.