Sydney Sweeney Gained 30 Pounds to Play Christy Martin in Biopic

Sydney Sweeney has offered a glimpse into the "crazy" transformation involved in her portrayal of pioneering female boxer Christy Martin in a new biopic, which involved gaining over 30 pounds.

"I loved it," she said of the behind-the-scenes training in an interview with W Magazine. "I came on board 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."

Sweeney also elaborated on the physical changes her body underwent as she prepared for the role.

"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," she said. "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."

Last year, Sweeney took to social media to share the first photos of herself as Martin, writing, "Here's a little bts from my film I'm working on right now."

"Over the past few months, I've been immersed in training to bring to life the story of an incredible woman — a true champion who fought battles both inside and outside the ring," she wrote, adding, "Her journey is a testament to resilience, strength and hope, and I'm honored to step into her shoes to share her powerful story."

Directed by David Michôd, the untitled biopic, based on a script co-written by Michôd and Mirrah Foulkes, will tell the story of Martin, the first major female boxing star in the U.S. It will chronicle her journey to stardom alongside the abuse she endured from her then-husband, who tried to kill her, Deadline reported.

"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," Michôd told W Magazine of the project.

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