The subtitle of this book is "Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer". The author describes the latest research on physical fitness in a very readable and engaging way and addresses lots of exercise myths about stretching (before cardio? after cardio? never?), exercise and weight loss, how long and how often to work out depending on your own goals, and more. Reynolds writes a fitness column for the New York Times and she is adept at making physiology, biology and neurology make sense for the lay person.