Brie Larson Pushed Her Body 'Far Beyond' Her Expectations While Training for Captain Marvel

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Brie Larson upped her fitness game to play Captain Marvel.

The Oscar winner, 32, went from being unable to "walk up a hill without being out of breath" to being able to do four, 400-lb. hip thrusts as part of her training for the title role in 2019's Captain Marvel.

"So, I started this journey thinking I'll get strong and I had no idea. I went far beyond what I ever believed was possible for my body," she told Insider.

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She added, "Being able to hip thrust 400 pounds, deadlift 200 pounds, push my trainer's Jeep, I mean, it's an incredible experience to realize what's inside of you is well beyond what you knew was possible."

Prior to joining the Marvel universe, the Room actress was not a big fan of the gym.

"I affectionately called myself 'an introvert with asthma' before I got to play Carol Danvers and I started training first out of sheer panic," she said.

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Taking on the superhero role was a gamechanger for Larson.

"That's part of why it's no surprise to me that this character has been able to reverberate outward, because she first and foremost changed my life," she added. "So it makes sense to me that she could change other lives too."

With the help of celebrity trainer Jason Walsh, Larson become "kind of obsessed" with her fitness routine — which she documents on social media — especially as she prepared to return to the role for the upcoming sequel, The Marvels.

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Larson has continued to push herself towards new goals while training for the second movie.

"When people say like, 'Oh, girls can't do that,' it just makes me wanna do it even more," she said. "So there were huge accomplishments this time and I just feel like my body's just getting more and more used to this and more and more excited."

Larson sees the parallels between her own fitness journey and her character's story arch.

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"In the first film she's developing that strength, and so I was developing my own personal strength with this one," she explained.

She continued, "She's already got more mastery over her powers. She can fly now. And so having my body more limber, more ready for these types of movements like wirework, which I didn't have to do as much on the first one, was the main goal."