Sydney Sweeney is used to challenging roles, but her latest transformation pushed her to the limit — physically and mentally. In a new interview with People, the 28-year-old actress revealed how she lost nearly 30 pounds (about 13 kilograms) in just seven weeks after filming Christy, a boxing biopic based on the life of champion Christy Martin.
“I had to be really strict with myself,” Sweeney recalled of dropping the weight she had gained for the role in such a short time.
The actress said gaining the weight in the first place was no easy feat. “When I was training, it was really hard to put on all the weight. I was eating so much food — like, everything you could possibly imagine,” she said. “And then I was downing protein shake after protein shake and taking a lot of creatine, which just makes you bloat.”
Once filming wrapped, she reversed her routine entirely. “When you stop working out and taking all your protein shakes, you lose muscle super fast,” she said. “It’s the first thing to go before fat. So, that, I dropped within two weeks.”
To regain her pre-Christy physique for upcoming projects — including the psychological thriller The Housemaid and the third season of Euphoria — Sweeney adopted what she called a “super clean” diet and ramped up her cardio. “I had to be really strict,” she said.
While she’s proud of the results, Sweeney made it clear she doesn’t plan to go through such an extreme transformation again. “This might be the one and only time I challenge my body this much for a role,” she said, adding that she’s thankful her “metabolism works really well.”
“I don’t want to say this is super easy,” she emphasized. “But I’ve been a very active person my entire life. Like, I was a super active kid, and I’ve always kind of just stayed active and always had a good metabolism. I can gain weight, but I can lose it too.”
Though Christy didn’t make major box office waves, the film — and the physical transformation behind it — have cemented Sweeney’s reputation as one of Hollywood’s most dedicated rising stars. “We don’t create art for numbers,” she has said previously. “We create to make an impact.”
Christy is now in theaters. The Housemaid, co-starring Amanda Seyfried, opens Dec. 19.