Sydney Sweeney is no stranger to reinvention, but her latest transformation may be the most extreme of her career yet. The Euphoria star stepped into the shoes of boxing legend Christy Martin in the new biopic Christy, which had its world premiere at the Toronto International Film Festival (TIFF).
Portraying Martin, one of the most celebrated female fighters of the 90s, required Sweeney to shed her on-screen image and step into a role that demanded significant physical change.
Sydney Sweeney's Weight Gain Journey
To convincingly play Martin, Sydney Sweeney underwent a remarkable body transformation. She gained nearly 13 kg (30 pounds) of muscle and weight. The actress revealed that bulking up was no easy feat. Working alongside a nutritionist, strength coach, and boxing trainer, she followed a rigorous diet designed to maximise her calorie intake.
"We upped my calorie intake, and I started taking a lot of protein shakes and supplements and eating everything. I ate a lot of Smuckers, a lot of peanut butter-jelly sandwiches, milkshakes, just constantly eating because we were so active. I was burning it all off at the same time, so keeping it up was a real challenge," Sweeney told Variety.
Her diet was paired with hours in the gym, where she worked to build a fighter's physique.
Training Like A Boxer
Sydney Sweeney didn't just look the part, she trained like a real professional athlete. She endured months of boxing drills, weight training, and sparring, often pushing herself to the limit with 12-hour shoot days followed by two additional hours of late-night training.
The physical toll was heavy. The actress admitted to suffering concussions, bruises, and even a black eye while filming fight sequences. "I was getting pummeled," she recalled. "I was getting knocked up. I had some gnarly bruises after that".
In one particularly challenging sequence, she recreated Christy Martin's fight with Laila Ali, taking real punches without using stunt doubles. "I wanted the fights to feel real," she explained.
Beyond The Boxing Ring
Directed by David Michod and co-written with Mirrah Foulkes, Christy dives deeper than Martin's achievements in the ring. The film also explores her abusive marriage to trainer Jim Martin, portrayed by Ben Foster, and the harrowing challenges she faced outside of boxing.
Adding authenticity to the production, the real Christy Martin was often present on set. She cheered Sydney Sweeney on during fight sequences, motivating her like a coach in the corner of the ring.