When former UFC fighter, James Wilks, tore ligaments in both of his knees in 2011, he set out on a mission to find ways to shorten his recovery time. He began scouring independent research from peer-reviewed science journals, and discovered niche historical facts about diet. He found out, for example, that the Roman gladiators subsisted primarily on a vegetarian diet. This and other information on nutrition surprised Wilks, and sent him on a bigger quest to understand if animal-based proteins were actually essential for his own athletic performance. Wilks’ personal journey to understand diet and protein became the genesis for The Game Changers, a new film from director Louie Psihoyos. The documentary—which aims to debunk some commonly accepted beliefs, especially in sports nutrition, about animal-based proteins—will premiere in Colorado at the Boulder International Film Festival on Friday, February 23.

The Game Changers focuses on Wilks’ six-year journey to understand diet and performance. During this odyssey, Wilks traveled to four continents and interviewed more than 50 elite athletes who keep a plant-based diet—including Arnold Schwarzenegger, American Olympian weightlifter Kendrick Farris, and Patrik Baboumian, a professional strongman with multiple world records. The documentary buttresses their testimonials with interviews from experts in nutrition, who explain the science behind their diet. True to Psihoyos’ reputation for shedding light on complex issues, the film tackles intrinsic cultural issues around animal protein. Take its mythical link to masculinity, for example. “To be a man you have to eat animal products, and if you don’t—you’re a wuss,” said Psihoyos. The research, however, shows that a man’s virility is actually increased by a plant-based diet. (You’ll have to watch the film for more on that.)

The Game Changers’ premiere in Boulder is a bit of a homecoming for Psihoyos. In 2009, the 25-year-resident of Boulder completed the documentary, The Cove, in his backyard. The documentary uncovered the controversial hunting of dolphins in Taiji, Japan. The film went on to win Best Documentary at the Academy Awards in 2010, and remains one of the most awarded documentaries of all time. By disclosing the toxic levels of mercury in dolphin meat, the film’s impact resulted in a dramatic reduction in the sale of dolphin meat in Japan. In fact, dolphin meat sales dropped by 60 percent in the first two years after the film’s release. With The Game Changers, Psihoyos has once again set out to change people’s hearts and their minds about nutrition. “I think the film will resonate with the people of Boulder. It’s one of the healthiest places in America and I think they are primed to hear this message,” said Psihoyos.

If you go: The Game Changers will screen at 4:30 p.m. on February 23 at the Boulder Theatre; Director Louie Psihoyos will be in attendance for a post-screening Q&A; tickets cost $13-$14. Find BIFF’s entire schedule here.