AceShowbiz - Florence Pugh became her own fitness trainer and nutritionist on the set of "Black Widow", because she wanted to be in charge of her look and what she put into her body to achieve it.

The defiant "Little Women (2019)" star refused to starve herself or spend hours and hours at the gym to portray Russian spy Yelena Belova in the new Marvel movie, so she told movie bosses she would take care of her own work-outs and diet, promising them she'd look good kicking butt in the film.

"When you think of Marvel, it's big and daunting, especially (for) a relatively small actor," she tells Elle Canada. "To look at it and go, 'Oh, I'm going to be a part of this!' - that's a big decision... Essentially, you need to look good moving."

"For me, I loved all of that because I grew up with a lot of dance and a lot of movement. I was always fighting my brother, so I find all of that combat stuff so exciting. Once you put it on camera, you've got to know how to make it look right, and that's a whole different beast."

"When I got the job, I wanted to know what the regimen was. I wanted to know whether it would be them or me calling the shots. That was a big deal for me. I didn't want to be part of something where I was constantly checked on and people were making sure I was in the right shape. That's not me at all."

And she took some nutrition tips from co-star Scarlett Johansson: "Scarlett had this amazing guy who cooked beautiful things for her and her team. I thought that was clever because you're doing fitness all the time and you need to have someone who's on top of what you're eating and the nutrients you're getting."

"I remember her asking, 'Why are you cooking for yourself? Just let us feed you!' I was like, 'Nope. My brain is so pew, pew, pew!' Genuinely, my therapeutic thing is chopping and cooking and stirring and tasting."