Joshua Jackson has revealed the extreme measures he took to gain 20 pounds for his latest role in Karate Kid: Legends. In an interview on the Today show, the 46-year-old actor admitted that he ate a staggering 4,000 calories a day to bulk up for his character, an ex-heavyweight boxer.

"I walk around at 175," Jackson explained. "I was almost 195 for the film." He added that he "put on all that weight" because his character, Victor, is an ex-heavyweight boxer. However, he was surprised to learn that bulking up wasn't as easy as he thought it would be. "It was harder than I thought it was going to be," he said.

Joshua Jackson's transformation didn't come without its challenges. The actor previously gained weight for a different role, telling The Hollywood Reporter in 2023 that he "went from 160 pounds to 190 pounds" while playing Christopher Duntsch in the Peacock true crime series Dr. Death. Unfortunately, Jackson said, he also suffered a back injury after working on the show, which he suggested was a result of the headspace he embodied as the corrupt neurosurgeon.

Related Stories

• Shai Gilgeous-Alexander Faces Off Against Cousin Nickeil Alexander-Walker in NBA Western Conference Finals
• Kaylor Martin Moves On From Dramatic Split with Aaron Evans, Debuts New Boyfriend Torin Dunn on Social Media
• Billy Ray Cyrus and Elizabeth Hurley Make Red Carpet Debut as a Couple in Rome

While Jackson said the 30-pound weight gain was "really not very good" for his body, he added, "But also carrying that kind of stress and anxiety around all the time is also not good for you."

Joshua Jackson's latest film, Karate Kid: Legends, premieres in theaters on Friday, May 30. Don't miss out on the latest celebrity news and updates. Sign up for our free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer.