Jack LaLanne's image—bouncy, cheerful, and muscular in a form-fitting jumpsuit—has been associated with health and fitness for over sixty years. Although he started his career in the 1930s at a time when people thought that exercising was odd or even dangerous, LaLanne practically invented the physical-fitness movement in the United States. A hot-tempered high school dropout from Bakersfield, California, mostly known for getting into fights and trouble, LaLanne discovered health food and body building at the age of fourteen and changed the course of his life.

In order to spread the word about how exercise could improve people's lives, LaLanne opened the first fitness club in the United States in 1936. He invented weight machines and exercise programs to help his customers learn to exercise. LaLanne was not only a pioneer in physical fitness but also a pioneer in the use of showmanship...