John Mathew Smith & www.celebrity-photos.com from Laurel Maryland, USA · CC BY-SA 2.0

Opened a gym called Slimmons in Beverly Hills that treated overweight people with encouragement instead of shame, then took that approach national through the Sweatin' to the Oldies aerobics tapes and years of frequent, self-mocking appearances on late-night TV. Beneath the shrieking persona was a serious advocate: in 2008 he testified before Congress for a bill requiring non-competitive physical education in public schools.