1 Jason Momoa Europa Press Entertainment // Getty Images Age: 46 Surprisingly, Aquaman isn't into hitting the gym to maintain his build—instead he prefers outdoor activities, like boxing, mountain climbing, and surfing. "It's very hard sometimes to just work out. It's monotonous and you can get stuck in a rut," he told Men's Health UK . 2 Chris Pratt Dave J Hogan // Getty Images Age: 46 After landing roles in Jurassic World and Guardians of the Galaxy , Chris Pratt transformed his build. The actor now follows a grueling workout routine , but the majority of his weight loss was the result of cutting out junk food and alcohol. "I probably lost about 35lb in six weeks. I ran five or six miles a day. I ate leafy green salads and protein shakes. I cut out all alcohol. Trim, trim, trim," Pratt told Men's Health UK . Advertisement - Continue Reading Below 3 Kevin Hart Rick Madonik // Getty Images Age: 46 Kevin Hart is known as one of Hollywood's hardest working comedians—and that includes in the gym.…