Part memoir, part scientific investigation, Racing the Clock is the book biologist and natural historian Bernd Heinrich has been waiting his entire life to write. A dedicated and accomplished marathon (and ultra-marathon) runner who won his first marathon at age thirty-nine, Heinrich looks deeply at running, aging, and the body, exploring the unresolved relationship between metabolism, diet, exercise, and age. Why do some bodies age differently...

For David Goggins, childhood was a nightmare--poverty, prejudice, and physical abuse colored his days and haunted his nights. But through self-discipline, mental toughness, and hard work, Goggins transformed himself from a depressed, overweight young man with no future into a U.S. Armed Forces icon and one of the world's top endurance athletes.