Darn near as old modern cinema itself, boxing has been the subject of many a movie over the years. Here, we see silent film star William Haines taking a breather in-between sparring. Most of us know that Haines was a major leading man (and close friend of Joan Crawford's) who left the biz rather than deny his homosexuality (and his longtime partner.) He went on to a successful second career as an interior designer.
Sterling Hayden was lauded for his looks and physique during his days as an actor. Though boating was his primary passion, he also spent time in the gym.
1960s rough and tumble cutie Robert Conrad boxed frequently in his off time to maintain his physique.
George O'Brien, a boxer in real-life prior to acting.