Zac Efron went through a massive physical transformation for Sean Durkin's The Iron Claw.

In a new interview, Efron dishes on the transformation. It was something that required a lot of dedication from the former High School Musical actor.

A “fascinating” experience

Kevin Von Erich next to Zac Efron playing Kevin Von Erich with the The Iron Claw poster as the background.

Speaking to Deadline, Efron revealed the process of his preparation for his Iron Claw role. In the film, he plays Kevin Von Erich.

“Nothing could prepare me for the wrestling,” Efron said with a laugh. “The physical preparation and the training, that's something that I've always found very interesting.

“I've always admired people's transformations, in particular for movie roles. I just find that dedication fascinating and special when I see it. So in training for this, I got to train essentially for my championship, my belt match. It all came down to, how precise is my training? How dedicated am I to this? How hard can I push?” he continued.

Efron then revealed that he may have “shed a skin somewhere in those seven months where Kevin was really at the wheel.”

He then claimed that it felt “real” to him. “It felt honest, it felt real,” Efron claimed. “I felt like I was physically there; I felt mentally there, as a direct result of the training, and then from there, the wrestling, surprisingly, was fun. It, in many ways, built the bond that we had as brothers for the movie.”

The preparation was a solo venture, Efron revealed. “I didn't really reach out to friends or family, and it was a very isolating process,” he said. “But about a week or two before filming, when we got to wrestling, as soon as we got into that ring, I made real brothers. There was this sense of encouragement and camaraderie that I hadn't felt in half a year, and I think it just generated a very sincere love and respect for those guys that weaves its way into the movie in the best way possible.”

The Iron Claw

The Iron Claw is Sean Durkin's wrestling biopic about the Von Erich family. Zac Efron leads the way as Kevin Von Erich with Jeremy Allen White and Harris Dickinson playing Kerry and David Von Erich. Maura Tierney, Holt McCallany, Lily James, and Maxwell Jacob Friedman also star in the film.