Scarlett Johansson's catsuit diet

How Scarlett Johansson shaped up for her Iron Man 2 role

Scarlett Johansson looks eye-poppingly good in her sexy catsuit in the new Iron Man 2 – but just exactly how did she get that smoking hot new body?

The actress has always been gorgeous, but she embarked on a low-carb, high-exercise regime to prepare for her latest role.

'I kicked some major butt,' the actress says of her prep to morph into a sexy, shapely superhero.

'It was many, many, hours, days, and months of stunt training and strength training, but it's fun because I had a goal. The goal was the Lycra catsuit.'

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'She was wearing an unforgiving costume,' said Johansson's Iron Man 2 director Jon Favreau.

'She didn't eat much, that's for sure. She likes food, as do I, and she was definitely on a low-carb diet and training very hard. It was amazing.'

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And how did Scarlett feel about the fab results? 'Finally I was, yes,' she said with a laugh. 'You put that much work into something and you put it on and you better be happy with it.'

And the star – who plays the Russian spy Black Widow in the film – had a few nods of approval from the crew: 'It was crazy to see it for the first time – everything all zipped up and all the weapons in there, bracelets on, the whole look. It was pretty sweet, I have to say,' she says.

'Certainly walking on set, because a lot of the people that worked on the film were fans of the comic and of course they knew the Black Widow – they were all super excited to see the Black Widow.

'When everybody in the crew were like, "That looks awesome!" I knew. Like, "Okay."'

The hard work definitely paid off.

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