Sydney Sweeney says the toughest part of her next film wasn’t stepping between the ropes—it was adding roughly 30 pounds of muscle for the chance to play trail-blazing prize-fighter Christy Martin in an untitled biopic directed by David Michôd.
In a W Magazine cover story she describes three daily training blocks—weights at dawn, two hours of kick-boxing at midday, and another hour of weights at night—that left her “so strong, like crazy strong,” even if her jeans jumped from size 23 to 27.
The physical overhaul is only part of the assignment. Michôd, who co-wrote the script with Mirrah Foulkes, calls Martin’s life “a wild mix of under-dog sports saga and personal ordeal” and says Sweeney “turned up every day with her tail wagging, ready to go”.
The film traces the West Virginia boxer’s rapid rise through the 1990s—she fought on a Mike Tyson under-card and became the first woman on Sports Illustrated’s cover—and the violence she later survived at the hands of husband-trainer Jim Martin.
That 2010 attack, which ended with Jim Martin’s attempted-murder conviction and a 25-year sentence in 2012, looms over the drama. Martin returned to the ring twice before retiring with 49 wins and three draws, securing her place in the International Boxing Hall of Fame. The boxer, now 56, recently rode beside Sweeney as grand marshal of the Hall’s Parade of Champions, underscoring her direct support for the project.
Production wrapped in November 2024, and industry trackers expect the picture to join the crowded 2025 awards calendar, although a distributor and release date have yet to be named. Anonymous Content, Black Bear and Fifty-Fifty Films are backing the film, whose cast includes Ben Foster, Merritt Wever and Katy O’Brian, according to production notes circulated during Sweeney’s October Instagram reveal. For the star, the rigorous camp offered something no couture shoot could: “I loved seeing what my body can do,” she told W.