Los Angeles, California - Black Widow star Scarlett Johansson is one of the best trained actors in the Marvel Cinematic Universe. What's her fitness secret?

Johansson revealed she has been swearing by pilates on The Skinny Confidential Him & Her podcast.

"I did weight lifting for a long time. That was my thing. I liked lifting heavy and low reps," Johansson said.

In 2019, the 38-year-old prepared for Avengers: Endgame by getting up as early as 6:00 AM to complete aggressive workouts that included plyometric exercises, heavy weight training, and intense cardio like sprints and battle-rope exercises.

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But eventually, Johansson switched up her routine to gentler fitness training options.

She ended up moving to pilates exercises for the film Black Widow.

"I got to an age when I was actually training on Black Widow, and you know, I think it's hard to lift heavy weights at a certain point," Johansson explained.

"You just, your body reacts in a different way than it [did] – the recovery is tough," she continued. "And so I started doing Pilates to try to give myself a break from some of the heavy weightlifting and I just fell in love with it. And now I do that mostly."

Johansson also assured fans that there are no secret celebrity health tricks: "There are no hacks to health and wellness."

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"I think for me personally, doing physical exercise as many times a week as I can do keeps me like mentally sane," she said.

"That goes a long way, 'cause I'm not getting as much sleep as I should be."