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For Olivia Munn, getting into shape for her role in "X-Men: Apocalypse" was hardly a walk in the park. It was more of a walk in the garden.

"I started getting into eating 20-80, where 80 percent of your diet is fruits and vegetables, and 20 percent is whatever," she told Women's Health magazine in its June issue.

Granted, diet was a big part of her body transformation, but there was also the physical aspect that she needed to turn into her Psylocke character.

"I started working out every single day," she said, adding that she did a lot of martial arts, even learning how to used a sword. It was "really empowering," she said.

Last June, the former "Newsroom" actress took to Instagram to show off her sword skills and they were pretty impressive.

When she was younger, Olivia participated in taekwondo, and was really good at it -- good enough to earn a black belt, in fact.

With her diet in check and her physical training, the actress saw the results in her waist line. She previously said she dropped 12 pounds while preparing for the film. The weight loss was never something she intended to do, necessarily.

"My intention was to just get as fit and as healthy as I could be, for myself," she said. "By the time I was finished [filming], I was 12 pounds less than I started!"

Also in the article, Olivia discussed why she likes to share beauty regimens. In February she credited potatoes for helping her look young. She's no stranger to people criticizing her beauty beliefs though.

"I think...when you're in the public eye, [scrutiny] does come with it," she told Women's Health. "People want to say things... My girlfriend, she said to me the other day, 'If people are wondering why you look younger, it's better than them asking why do you look older.'"

She continued, "A lot of times, people want to hoard their secrets to themselves. But whenever I learn things now...I want to tell anyone who wants to listen about them, because I don't think guys are the only ones who should be able to look better as they age."