“Sprinters typically look powerful, bursting with energy and eager to push themselves to their limits. The explanation is simple. No matter how intense the demand they face, the finish line is clearly visible 100 or 200 meters down the track. We, too, must learn to live our own lives as a series of sprints—fully engaging for periods of time, and then fully disengaging and seeking renewal before jumping back into the fray to face whatever challenges confront us.”