Racing the Clock: Running Across a Lifetime – A Natural Historian Explores Metabolism, Diet, and Overcoming Aging

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 lifetime

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 than others? How much control do we have over that process and what effect, if any, does being active have? Bringing to bear research from his entire career and in the spirit of his classic Why We Run, Heinrich probes the questions of how we use energy and continue to adapt to our mutable surroundings and circumstances. Beyond that, he examines how our bodies change while we age but also how we can work with, if not overcome, many of these changes—and what all this tells us about evolution and the mechanisms of life, health, and happiness.

Racing the Clock offers fascinating and surprising conclusions, all while bringing the reader along on Heinrich’s compelling journey to what he says will be his final race—a fifty-kilometer race at age eighty.

Blending a lifetime of scientific inquiry with the raw data of his own body, Heinrich reveals the intricate dance between physiology and time.

The Biological Clock: Heinrich examines how circadian and circannual rhythms govern not just our energy and adaptation, but the very pace of our lives. A Scientist's Memoir: From running his first marathon at thirty-nine to setting world records as a masters athlete, Heinrich uses his own life as the ultimate field experiment. The Science of Running: Explore the physiology of endurance, from the role of metabolism and diet to how the body adapts, repairs, and ultimately succumbs to the stress of long-distance running. Endurance and Aging: Follow Heinrich's compelling journey as he prepares for a fifty-kilometer race at age eighty, testing the very limits of what is possible in the race against time.