ET's Rocsi Diaz recently sat down with Mark Wahlberg, Dwayne Johnson and Anthony Mackie in Miami to talk about their new Michael Bay film Pain & Gain, specifically all the physical dedication it took to play bodybuilders who get caught up in an extortion ring and kidnapping scheme that goes horrifyingly awry.
"It was fun for the first couple of weeks but then it became pretty difficult because you're just constantly eating, training," Wahlberg says about the grueling routine. "And I would go to bed at nine o'clock after just having a meal, and I'd wake up at 12 again to eat again, so that was probably the most difficult part."
Pics: Shocking Movie-Role Body Transformations
But it turns out Wahlberg's kids, specifically his son, took a liking to all the muscles.
"Well after the movie, I started to lose all the weight for another movie, and my son was like, 'Don't lose weight dad' -- my four-year-old -- and I was like 'Dude,'" he jokes.
Mackie's son was equally fascinated with the normally lean actor's body transformation.
"It was hilarious, when my family came down and everybody saw me, and my son was like 'Woah dad, you're big,'" he laughs. "And every morning he would come and jump on the bed, and squeeze me and touch me and poke me."
"I would do the same thing," Johnson jokes about Mackie, who stayed at his Miami home.
Video: Their 'Pain' is Your 'Gain'
One thing the obviously close cast does feel bad about?
Constantly having to "beat up" Tony Shalhoub, who plays kidnapping victim Victor Kershaw.
"It wasn't until the end you realize he was such a trooper, he never complained once about what was happening," Wahlberg says. "And I have a tendency to ramp it up a little bit when I'm the giver -- I'm not good at receiving pain and beating -- but he was such a trooper, he never complained."
Check out the video to hear about how Miami native Johnson felt about portraying such a notorious real-life story, and Wahlberg dish on his upcoming Transformers role.
Pain & Gain hits theaters April 26.