3. Paul Rudd
Action movies expect nothing less from their stars than to be in great shape throughout the entire filming process. To bring his best performance to the movie Ant-Man, Paul Rudd needed to build a fit and athletic body, removing anything enjoyable from his diet and focusing on intense exercises every day for a year. Playing a hero comes with sacrifices, after all.
4. Mark Wahlberg
Given 2 months to prepare for his role in the movie Pain & Gain as a bodybuilder, Wahlberg was keeping busy catching up in size to his co-star Dwayne Johnson. He packed on as much as 40 pounds eating up to 10 meals a day. Even though he has eased off a bit, the hard work he put into bulking up is still visible every time he appears on-screen.