An award-winning, much-loved biologist turns his gaze on himself, using his long-distance running to illuminate the changes to a human body over a lifetimePart 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