LaLanne, Jack (ləlānˈ) [key], 1914–2011, American fitness advocate and television personality, b. San Francisco as François Henri LaLanne. Widely regarded as the founder of the modern fitness movement, he began working out with weights as a young man, went to chiropractic school, and in 1936 opened a gym, juice bar, and health food store. The Jack LaLanne Show, the first television exercise program, debuted (1951) in San Francisco. After it went national, he became a fitness celebrity, famous for advocating exercise, a proper diet, and the consumption of raw juices. LaLanne was also a pioneer in creating fitness machines.