“Nothing about the biology of exercise makes sense except in the light of evolution, and nothing about exercise as a behavior makes sense except in the light of anthropology.” In this myth-busting book, Daniel Lieberman, professor of human evolutionary biology at Harvard University and a pioneering researcher on the evolution of human physical activity, tells the story of how we never evolved to exercise — to do voluntary physical activity for the sake of health. Using his own research and experiences throughout the world, Lieberman recounts how and why humans evolved to walk, run, dig, and do other necessary and rewarding physical activities while avoiding needless exertion. As our increasingly sedentary lifestyles have contributed to skyrocketing rates of obesity and diseases such as diabetes, Lieberman argues that to become more active we need to do more than medicalize and commodify exercise. Shermer and Lieberman also discuss: evolutionary and anthropological perspectives on physical activity, why we never evolved to exercise, physical activity vs. exercise, sleep: how much do we really need? walking vs. running; speed vs. strength, endurance and aging: why exercise matters, why we age and die, exercise and diet, Should we do weights, cardio, or high-intensity training? Is sitting really the new smoking? Is BMI really a useful measure? exercise and disease: obesity, diabetes/metabolic syndrome, cardiovascular disease (and cholesterol), osteoporosis, Alzheimer’s, depression, and cancer, immune systems and exercise, and How much exercise should you get each week? Daniel E. Lieberman is Edwin M. Lerner Professor of Biological Sciences and professor of human evolutionary biology at Harvard University. He is the author of the national best seller The Story of the Human Body: Evolution, Health, and Disease. He lives in Cambridge, Massachusetts.