Sydney Sweeney recalls being "crazy strong" while playing Christy Martin in upcoming biopic

By Sophia Soto | Last updated Jun 11, 2025 9:58 AM ET

Sydney Sweeney is opening up about her role in the upcoming biopic film about Christy Martin, which, according to Deadline, will "chart the true story of Martin’s rise to become America’s most well known female boxer in the 1990s — the 'female Rocky' in the words of the film’s producers."

The actress actually has a passion for boxing and MMA: "I grappled and did kickboxing from 12-19 years old. I’ve been itching to get back into the ring, train, and transform my body. Christy’s story isn’t a light one, it’s physically and emotionally demanding, there’s a lot of weight to carry. But I love challenging myself."

She continued to express, "Christy Martin not only legitimized female boxing, she overcame gender stereotypes, and fought through emotional, physical, and financial abuse. I’m passionate about the fighting world, Christy’s story shines a light on her incredible rise to the top while showing the struggles of fame behind the curtains. I feel compelled to tell a story about a woman who faced so much adversity and didn’t allow it to defeat her. It’s powerful, and emotional."

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The role required her to gain over 30 pounds. "Martin put female boxing on the map in the mid-’90s," director and co-writer David Michôd told W. "She was the first woman fighter on the cover of Sports Illustrated and fought on the Mike Tyson undercard. Her husband was also her trainer, and then, after her success, he tried to murder her. Our film is a wild mix of inspiring underdog sports-world story and personal saga. Sydney trained her butt off to play the part. The beauty of Sydney is that she turned up to work every day with her tail wagging, ready to go. No matter how tough it was, she was like a ray of sunshine."

Sweeney commented that she "loved it," adding, "I came onboard to play Christy, and I had about three and a half months of training. I started eating. I weight-trained in the morning for an hour, kickboxed midday for about two hours, and then weight-trained again at night for an hour."

As for the physical transformation, she explained, "My body was completely different. I didn’t fit in any of my clothes. I’m usually a size 23 in jeans, and I was wearing a size 27. My boobs got bigger. And my butt got huge. It was crazy! I was like, Oh my god. But it was amazing: I was so strong, like crazy strong."

The movie will be released this fall.

Sophia Soto

Sophia Soto is a writer and interviewer with a passion for all things entertainment. She is a Senior Reporter at The Nerds of Color and contributes to Yardbarker, Screensphere, Den of Geek, What to Watch, Nerdtropolis, and Temple of Geek. You can see her past work on Remezcla, Young Hollywood, Looper, Paste Magazine, Primetimer, Soundsphere, and Starry Constellation Magazine

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