Brie Larson had to go for several fittings on the lead up to filming 'Captain Marvel' because her body shape kept ''changing''.

The 29-year-old actress - who stars as the titular character in the new Marvel movie - hit the gym hard to prepare for her role as the extraterrestrial Kree warrior, but as a result, she ''repeatedly'' had to visit the wardrobe team to make sure her on screen outfits fit her correctly because she ''worked out like crazy''..

Speaking to Vogue UK, costume designer Sanja Milkovic said: ''We want to see women on screen, especially women that are so strong and so powerful. I'm so happy to be part of this.

''She [Brie] was working out like crazy - I'm so in awe of her.

''Her body was changing, as expected, so she was coming in repeatedly for fittings.

''Over the course of working out she was finding out more and more what her action scenes were going to be, and so we were making sure what we were doing would allow her to do certain things.''

Brie debuted as her Marvel alter-ego wearing the iconic blue and red superhero suit, and Sanja set out to make the costume both ''attractive'' and ''strong''.

She added: ''Her suit is strong and super-heroic, but still very feminine. It was a conscious decision to not just make her a gorgeous, beautiful thing but instead make her costume part of her attitude. She's a girl with an attitude and rightfully so; she has nothing to prove. It's a very modern concept for a female superhero. Hopefully a lot of young women can relate to that.

''It had to be period, but it had to be attractive to the audience today. She's a pilot and a tomboy, so what would a young woman like that wear? And she's a big rock'n'roll girl. So, a combination of rock'n'roll and grunge was obviously the way to go.''