Olivia Munn unintentionally dropped 12 pounds filming 'X-Men: Apocalypse'

All those grueling workouts definitely cost Olivia Munn... to the tune of 12 pounds!

The gorgeous actress has been keeping fans up to date about the difficult workouts she's been taking on while filming "X-Men: Apocalypse" and apparently it helped her shed a lot of weight.

"It was not intentional. I was trying to learn how to do all of the stunts," Munn began to explain during an interview with E! News during the film's London press junket.

"My character's the last to be brought into the story. They weren't expecting Psylocke to do a lot of fighting in the movie, but when I had signed on, I said that's something that I really wanted," she continued.

But there was a catch! The film crew brought in a stunt person, who Munn says was "super talented and very athletic," but she had never done any martial arts or fighting.

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Naturally, the 35-year-old actress decided to take on the challenge herself.

"She was very capable and very athletic, but she had never done any stunts before, and I had grown up doing Taekwondo. I'm like, this is Psylocke's entry into this world, I'm not Jennifer Lawrence, if they don't have it, they're not gonna make sure to get it in there somehow. If there's not a fight scene being shot, if they don't have it, they're not gonna use it."

"If I wanted the fans to see Psylocke and get a good fight scene for her and the fans, I knew I had to go do it myself. So I started training every day with Taekwondo and sword and the stunt and wire work, and I just ended up losing 12 pounds from working out every day."

Munn definitely looks sleek and svelte as one of the newest members of the "X-Men" cast. Although she admitted she didn't keep the weight off for long, opting to eat chips and salsa with her boyfriend as soon as she was off set.

Either way, now we know how to work on our bikini bods this summer-- martial arts.

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