Russell Crowe gained 63 lb. for the 2008 movie "Body of Lies" but then had a tough time getting all that weight off. Recently he got himself on a grueling health regime that involved 105 days of training and a diet restricted to 2,400 calories a day. "If i stop exercising my body tries 2 return 2 its heaviest weight," he tweeted to a fan. (Getty Images)