Mark Wahlberg is known to be a beast in the gym. Not too long ago the actor was posting videos to Instagram of his 2:30 a.m. workout call time. However, now it seems that the 49-year-old has ditched his intense gym sessions and is eating a lot more than usual to gain weight.

On Monday, Wahlberg posted a side by side photo of himself from three weeks ago compared to now. The photo on the left showed the ‘Patriot’s Day’ actor sporting a six pack wearing boxing shorts and the picture on the right was of Wahlberg today after gaining 20 pounds. The actor captioned his photo saying, “From this 3 weeks ago, to this, now. Thanks to @chef_lawrence_d cooking.”

The reason for Wahlberg’s body change is the movie role he’s playing in an upcoming film by Mel Gibson’s girlfriend, Rosalind Ross. The actor told Jimmy Kimmel about the new film when he appeared on the late night talk show last week. “I‘m playing a guy who was a fighter—he was many things,” Wahlberg said.

“He was a fighter, he moved to L.A. to become an actor, he fell in love with a girl, he had an accident, he had an outer-body spiritual experience, he decided to become a priest. He died of a rare disease, IBM, but he had a big impact on a lot of people in a very short amount of time,” the 49-year-old continued.

Wahlberg had abs a few weeks ago because he had to be in shape for when he was playing the character as a boxer. Then as the character’s life changed, the actor had to gain weight.

“After we do the boxing scenes, I get to put on as much weight as possible over the course of the film, so I‘m challenging myself to put on 30 pounds in the next six weeks,“ he revealed. “They want me to do it as healthy as possible. I’m like, ‘Dude, I’ve been on such a regimen for so long, I just want to eat everything in sight.’ I want to go to bakeries, I want to go to Denny’s, I want to get pancakes. I want to get everything that I could possibly get my hands on,” he said to Kimmel.