Blake Lively gave birth to her first baby, daughter James Reynolds, in December 2014, and ten months later, she was looking fit as ever in a bikini in her shark attack film, The Shallows. But when the 28-year-old actress signed on to the film, she wasn’t yet bikini-body ready: Lively accepted the challenge, and then lost the baby weight by training for the film.

“I do not look like that in real life. That was an eight-week period of my life,” she said on Live with Kelly on Wednesday morning of her incredible figure. “I’m lucky to have an amazing trainer, this guy Don Saladino, who just kicked my butt. That movie was an athletic event as much as it was an acting job. We didn’t hire a stunt double until the last two weeks, so it was just like insane, underwater stunts.”

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But make no mistake, her acting skills kicked in when she had to pretend to battle a terrifying shark—who was actually just a man with a shark fin. The real villain of the set was a seagull who kept pecking at Lively’s fake battle scars. “It was actually the bird that was attacking me all the time though, because he loved the taste of my prosthetic wound, so he would always come for me. So if you ever see terror on my face, it’s not the shark—it’s this bird who was just like attacking me at all times. And probably the terror that I hadn’t eaten bread in too long,” she joked of her intense diet. “No gluten, no soy. That’s what it was.”

While it was certainly restrictive, the diet definitely paid off. Now pregnant with her second child, Lively is free to indulge. Watch the clip above for the expectant star’s full interview.