How Jharrel Jerome Got ‘Most in Shape Ever’ to Play Wrestler in Unstoppable (Exclusive)

Unstoppable demanded Jharrel Jerome put in a lot of work to become wrestling champion Anthony Robles. Much of it is right there on screen, from wrestling to lifting to weighted running — often on crutches, as Robles was born without a right leg.

“I’m the fittest I’ve ever been in my life,” the actor, 27, tells PEOPLE. Grimacing, recalling his grueling training regimen, he wryly adds, “so it’s great.”

Unstoppable tells the incredible story of Arizona State University alum Robles, now 36, who became an NCAA champion in 2011 after launching a wrestling career in high school. Jennifer Lopez, Bobby Cannavale and Don Cheadle play real-life characters in Robles’ life.

To recreate his fights in the ring, Jerome and Robles himself (a stunt double and consultant on the film, producing with Ben Affleck and Matt Damon) followed choreographed movements in exacting detail. That meant not only training to match Robles’ athleticism, but also refreshing knowledge of the sport, explains Jerome.

“WWE was about all I knew when it came to wrestling,” the When they see us The Emmy winner admits.

Seam Unstoppable Lingering in development and then interrupted by 2023’s writers’ and actors’ strikes, Jerome endured months of bootcamp: “Nine to 5, five days a week,” he recalls. “On the last day of our boot camp, we went right into day one of shooting, which was pretty crazy.”

Of course, he “couldn’t slide” when the cameras started rolling. “I skipped all my lunch breaks” to work out, he says. “I packed meals and microwaved them throughout the set and ate between meals. Because everyone would go to lunch and I would go into whatever facility they had nearby, whether we were on a college campus or in a warehouse, where they would bring in weights and a mat so I could body work.”

While Jerome says it’s hard to pick the biggest challenge in “transforming and becoming the beast” he jokingly calls Robles, calluses under the armpits from constant use of crutches are high on the list.

“I practiced moving around on crutches so I can’t look like I just sprained my ankle two weeks ago,” says the actor, who wore a green sock that erased one leg via special effects.

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It was all worth it for his connection with Robles, who invited cast and crew members into his Arizona home throughout filming. “I consider him a brother,” says Jerome. “It’s really gone beyond work for us.”

Plus he is now never short of inspiration to continue to stay in shape. “It’s 8 in the morning and I don’t want to wake up, but I’m up in the gym at 8:30 and it’s just because I know Anthony would be,” says Jerome. “You can’t see someone do 80 pull-ups with a weighted vest like Anthony does and not use that as motivation.”

Unstoppable now streaming on Prime Video.