Sydney Sweeney’s transformation into boxing legend Christy Martin for the biopic Christy has left fans and critics stunned, as the actress revealed the grueling physical and emotional toll of her preparation. In a candid interview at the Toronto International Film Festival, Sweeney disclosed gaining 13 kilos (30 pounds) through an intense regimen of weight training, kickboxing, and a high-calorie diet, including Chick-fil-A and milkshakes. The Euphoria star, known for her glamorous roles, described enduring brutal beatings during filming, including a “crazy black eye” from recreating Martin’s 2003 fight against Laila Ali, sending shockwaves through the audience and sparking a frenzy on X.
To embody Martin, the first female boxer inducted into the International Boxing Hall of Fame, Sweeney committed to three and a half months of training, lifting weights for an hour in the morning, kickboxing for two hours midday, and training again at night. “My body was completely different,” she told W Magazine. “I didn’t fit in any of my clothes. My jeans went from size 23 to 27. My boobs got bigger, my butt got huge!” The 13-kilo gain, guided by a nutritionist and boxing coach, left her “crazy strong,” but the physical demands were relentless. Filming all fight scenes in one grueling week, Sweeney endured real punches, with ice packs on standby between takes for bruises and concussions.
The film, directed by David Michôd and set for release on November 7, 2025, chronicles Martin’s rise as a pioneer in women’s boxing and her survival of domestic abuse, including a 2010 attack by her husband, Jim Martin, who stabbed and shot her. Sweeney’s commitment extended beyond the physical, as she immersed herself in Martin’s emotional struggles, earning praise from the boxer herself, who visited the set. “Sydney was a perfectionist,” Martin told DailyMail.com, commending her authenticity in portraying both the fights and the abuse. Fans on X lauded Sweeney’s dedication, with one posting, “She took real hits to tell Christy’s story—Oscar-worthy!”
However, the transformation wasn’t without controversy. Sweeney faced body-shaming comments during training, prompting her to share workout footage on Instagram, showcasing moves like tyre flips and boxing drills. “I’ve been immersed in training to bring to life an incredible woman,” she wrote, silencing critics. The intense process took a toll, with Sweeney admitting to Variety that filming 12-hour days followed by two-hour training sessions was “exhausting.” Yet, she embraced the challenge, saying, “I’m glad Christy’s story is being told.”
As Christy garners Oscar buzz, Sweeney’s transformation—marked by physical sacrifice and raw authenticity—has redefined her as a serious actress. The boxing world and fans alike are captivated, with posts on X calling her “a warrior in and out of the ring.” Whether she secures an Academy Award or not, Sweeney’s brutal journey to become Martin has already cemented her as a force, proving her mettle in one of cinema’s most demanding roles.
