Sydney Sweeney said a diet heavy on fast food and milkshakes, combined with intense physical training, helped her transform for the lead role in the new film Christy, which premiered Friday at the 2025 Toronto International Film Festival.
During a post-screening question-and-answer session at TIFF, the 27-year-old actress described gaining more than 30 pounds to portray boxer Christy Martin. "I trained for two or three months before [filming]. I had a boxing coach," she said in remarks shared on social media. "I had weight trainers, I had nutritionists. I trained three times a day, every day. And then while I was filming, I trained as well."
Director David Michôd and Sweeney both highlighted the unconventional eating regimen that accompanied the training. "And there was a lot of Chick-fil-A," Michôd said, prompting Sweeney to add, "A lot of Chick-fil-A, a lot. A lot of Smucker's, a lot of milkshakes, a lot of protein shakes."
Sweeney said the work to inhabit Martin's physique went beyond weight gain, emphasizing a regimen of boxing and strength training to capture the athlete's physicality. The comments came as the film, titled Christy, was introduced to festival audiences; Michôd directed the feature.
Christy Martin is widely regarded as a pioneering figure in women's boxing, rising to prominence in the 1990s and helping raise the sport's profile. The film portrays her career and public profile, and the role required Sweeney to adapt both her body and her boxing technique to reflect Martin's style and presence in the ring.
Sweeney's remarks at TIFF offered a glimpse into the practical and dietary choices made to achieve a dramatic physical transformation for a biographical role. She and Michôd framed the approach as a combination of professional coaching, careful oversight from nutritionists, and calorie-dense meals and shakes to meet the production's requirements while maintaining the performance's physical authenticity.
The film's festival reception and further release plans were not detailed during the Q&A. Festival premieres often serve as the first public showing before broader distribution decisions are announced by filmmakers and studios.