Sydney Sweeney Ate ‘a Lot of Chick-fil-A’ to Play Female Boxer Christy Martin

Sydney Sweeney went the distance to fully embody female boxer Christy Martin in the powerful new biopic Christy — and that involved eating a lot of Chick-fil-A.

Following the film’s world premiere at the Toronto International Film Festival’s Princess of Wales Theater on Friday, Sept. 5, Sweeney, 27, recalled the physical demands of playing the athlete, whom she affectionally called “the greatest boxer in the entire world.”

Standing next to Martin, 57, onstage, Sweeney said, “I trained for two or three months before I had a boxing coach. 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.”

“And there was a lot of Chick-fil-A,” added director David Michôd. Sweeney confirmed, adding that her diet also consisted of “a lot of Smucker’s, a lot of milkshakes, a lot of protein shakes.” “But it was incredible being able to completely embody such a powerful woman,” she concluded.

The first audience to see Christy gave the film a standing ovation, drawing an emotional reaction from Sweeney.

“As you can tell, she’s such a special and incredible human being, and her story deserves to be told,” the Euphoria Emmy nominee told the crowd, fighting back tears. “Christy, you are absolutely incredible, and I’m so honored,” she told the former professional boxer. 

“Being able to have her by my side during this process was a dream — but then also just scary too,” she said. “Because you’re like, ‘Oh, my gosh, we’re doing this in front of her.'”

Following its rapturous reception in Toronto, Christy will debut in theaters Nov. 7. Directed by Michôd, who co-wrote the script with Katherine Fugate and Mirrah Foulkes, the movie tells the story of Martin’s rise in the boxing ring throughout the 1990s and her struggle with domestic abuse. 

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On the red carpet before the premiere screening, Martin told PEOPLE it was “awesome” to share such an experience with the Anyone But You star. “It was one thing to be in a Tyson fight,” she quipped. “It’s another thing to be at a premiere with Sydney Sweeney.”

In July, Black Bear Pictures shared the first official photo of Sweeney as Martin. The distributor will release Christy in theaters on Nov. 7.