Deena Kastor was a star youth runner with tremendous promise, yet her career almost ended after college, when her competitive method—run as hard as possible, for fear of losing—fostered a frustration and negativity and brought her to the brink of burnout. On the verge of quitting, she took a chance and moved to the high altitudes of Alamosa, Colorado, where legendary coach Joe Vigil had started the first professional distance-running team. There she encountered the idea that would transform her ...