Scarlett Johansson has admitted that it was her Iron Man 2 costume that was the driving force behind getting fit for the movie.
The actress takes on the role of undercover spy Black Widow in Jon Favreau's second Iron Man movie, which sees Robert Downey Jr return to the role of Tony Stark.
Speaking to the Independent the actress said: "One of the biggest motivators was when I first saw my costume - the Lycra catsuit; the first time I saw it, I was like, 'If I've gotta get into that thing, I better start now'.
"The challenge was to get in the suit and believe it.
"It's been an empowering experience, which has made me feel much stronger than I've ever felt before," she continued.
"I did a lot of weight-training, mixed martial arts and hand-to-hand combat. When you're working out that much, you also have to feed your new body, so you eat in a different way, very clean, lots of omelettes, turkey and stuff like that."
And Johansson admits that she was sad to say goodbye to the costume: "I wish I could have kept it afterwards but unfortunately it's the property of Marvel so, after I took it off for the final time, I said, 'Ta-ta for now. I love you! Hopefully I'll see you in the future'."
Iron Man 2 will be the first movie for Johansson since starring in He's Just Not That Into You back in 2009.
Iron Man 2 is released 30th April.
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