Putting on weight wasn’t easy for Mark Wahlberg.

On the “Kyle and Jackie O” radio show in Australia, the actor talked about having to put on pounds for his role in the upcoming boxer-turned-priest drama “Father Stu”.

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“I would say it’s easier to stay in shape than it is to get in shape,” Wahlberg said. “I put on 30 pounds… that was really difficult. I’m not getting younger.”

On his Instagram account, the actor kept fans updated on his progress getting his body ready for the movie.

In “Father Stu”, which premieres April 15, Wahlberg plays real-life Father Stuart Long, who turned his life of self-destruction in the world of boxing into a life of redemption in pursuit of the priesthood.

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At the same time, Father Stu battled inclusion body myositis, a serious autoimmune condition.

The film was shot in just 30 days in May 2021, and Wahlberg has talked about his diet for the film, in which he reportedly ate up to 7,000 calories a day to gain weight.