Captain Marvel's Brie Larson reveals the biggest concern she had about joining the Marvel Cinematic Universe in 2019. Not long after winning an Academy Award for her performance in 2015's Room, Larson was tapped to play Air Force fighter pilot Carol Danvers in the MCU. Her debut came in the solo film Captain Marvel, which, despite mixed reactions from audiences, was met with largely positive reviews from critics and grossed over $1 billion at the box office, leading Marvel Studios to begin developing a sequel.

Since her debut in 2019, Larson's Captain Marvel has been regularly present in the MCU, showing up twice during Avengers: Endgame and once during Shang-Chi and the Legend of the Ten Rings' post-credits scene. Her most recent MCU appearance was Ms. Marvel's mid-credits scene, which sees Carol Danvers switch bodies with Iman Vellani's Kamala Khan, setting up the events of the upcoming Captain Marvel sequel, officially titled The Marvels. That film will feature the trio of Captain Marvel, Ms. Marvel, and Monica Rambeau (Teyonah Parris).

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During a recent appearance on Jimmy Kimmel Live to promote a couple of new projects - the short film Remembering and her new Disney+ series Growing Up - Larson reflected on being cast as Captain Marvel. As a self-described "introvert with asthma," Larson was very apprehensive about the role's physical demands, leading her to become a workout fanatic in order to cope with the fear. Read what she shared below:

Pure fear [of] failure. I thought that I was like supposed to do my own stunts. They casted me and I was like, "They low-key don't understand that I'm an introvert with asthma, like, they made a mistake... I got to figure this out real quick." So I started training, and I learned that I was actually much stronger than I realized, and that my allergies were what was causing my asthma. So, I just took allergy medicine. And I could lift heavy weights and it really transformed my life. And Captain Marvel changed me as a person way more than I ever [would've thought].

Brie Larson Captain Marvel 2 Workout

It's completely understandable that Larson's insecurities led to some reservations about joining the MCU. For starters, Captain Marvel was the studio's first female-led superhero film, which naturally put tremendous pressure on whoever was cast in the role. In addition, Captain Marvel is frequently touted as the strongest Avenger in the MCU, above Scarlet Witch, Doctor Strange, Hulk, and Thor. Thus, Larson had to begin a rigorous workout regimen in order to look the part of a superhero.

Larson's commitment to meeting the physical demands of her role as Captain Marvel has been apparent on social media in the past few years, with her frequently documenting her workouts and sharing them with followers. The fact that Larson not only overcame mental obstacles, but physical ones like asthma, adds another inspirational layer to these workouts that garner so much attention online. Unless she pops up in another post-credits scene, Larson's next scheduled MCU appearance will be in The Marvels, releasing next summer.

Source: Jimmy Kimmel Live/YouTube

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