Mark Wahlberg Reveals his ‘Pain & Gain’ Prep for Movie Roles

Sarah Flanigan
omg! Celeb News

Mark Wahlberg stopped by "Jimmy Kimmel Live" Tuesday night to promote his upcoming flick "Pain and Gain," which is about a pair of steroid-abusing Floridian bodybuilders who get caught up in an extortion and kidnapping scheme. With four films in the last year, the hunky Hollywood A-lister had to endure quite a crazy lifestyle in order to lose and gain weight quickly for each role.

[Related: Boston Native Mark Wahlberg Sends Prayers After Marathon Bombings]

"It's funny because when I was training for the movie, I was 165 pounds," he explained. "I did four movies last year. For the first movie, I had to get as thin as possible. For this one, I had to get as big as possible -- then I had to lose the weight in 30 days. I went from 165 to 212, and then I went back down to 180 in 30 days, and then I went to SEAL training and did a movie afterwards, the Marcus Luttrell film ["Lone Survivor"]."

So, how exactly did he do it? The 41-year-old actor ate 10-12 meals a day and loaded up on supplements.

"I started eating whatever I wanted, so I was eating pancakes and stuff and that was fun, " he admitted. "But I was also developing my own supplement line, so I had access to the scientists that GNC provided me. I was getting all the best ban-free substances -- whey protein, mass gainer, my blast and burn packs," he revealed.

When Walhberg wasn't hoarding loads of food or shooting, he slept.

"They call them growth naps," he said. "You workout in the morning really hard and then you eat throughout the day. Then, you just nap. You're either resting or eating."

Eat whatever you want and take lots of naps to look THAT good? Sign us up! Check out the video to find out more about Mark's beefy bodybuilding ways, and be sure to tune in to "omg! Insider" on TV tonight for more of the buzziest entertainment news.

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