Chris Mosier stars in an inspiring new Nike ad that praises his “unlimited courage” as the first transgender Team USA athlete. The spot will first air during NBC’s coverage of the Rio Olympics later on Monday, August 8.

In the 30-second clip, the duathlete is asked a series of questions: “How did you know you’d be fast enough to compete against men? Or strong enough? … How’d you know the team would accept you? Or that you’d even be allowed to compete?”

After each question, Mosier replies, “I didn’t,” as he runs, bikes and works out as part of his training for the U.S. men’s national team. 

In an interview with Nike, Mosier said that at age 4, he was already aware that his gender identity as a male didn’t align with his biological sex as a female.

“Everything that I’ve done in the last five, six years since I started to transition, has been with [a] ‘Just Do It’ mindset,” he said of the company’s famous slogan. “I didn’t know if I would be competitive against men; I just did it. … I’ve learned a lot about myself and also had the opportunity to further the conversation on trans inclusion in sports.” 

Once Mosier qualified for a spot on the team in 2015 at the national championships, he had to challenge the policies on transgender competitors and fight for more inclusive guidelines, which the International Olympic Committee adopted in January.

“Being the first trans man on a U.S. men’s national team was a dream come true for me,” he said. "I always wanted my name on a jersey. To represent our country at the highest level, in my sport, is just outstanding. It’s just such an amazing opportunity — and an amazing opportunity for other people to see themselves reflected in someone succeeding in sports as a trans man.”

Watch the video above! 

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