Chris Mosier – the first out transgender athlete to qualify for a U.S. national team – made history again

Chris Mosier doesn’t know how to quit.

The transgender duathlete inspired many, when he became the first out transgender athlete to qualify for a U.S. national team. And now, he’s showing off his ultimate courage in a new Nike commercial.

Though he’s not competing in the Olympics this time around, the 35-year-old runs, bikes, and works out in the 30-second spot – all part of his training for the U.S. men’s national team.

“How did you know you’d be fast enough to compete against men?” he’s asked in the video, via voiceover. “Or strong enough? How’d you know the team would accept you? Or that you’d even be allowed to compete?”

After every question, Mosier answers with a simple “I didn’t.”

“That must have been tough?,” the voiceover says. “Didn’t you ever just want to give up?”

“Yeah, Mosier responds. “But I didn’t.”

The ad aired during the 2016 Summer Olympics primetime coverage Monday night – Nike’s first-ever ad with a transgender athlete. It’s part of the company’s “Unlimited” series, which highlights “everyday athletes and the champion athletes who regularly push their limits,” the campaign’s website says.

“Everything that I’ve done in the last five, six years since I started to transition, has been with [a] ‘Just Do It’ mindset,” Mosier said, of the campaign. “I didn’t know if I would be competitive against men; I just did it.”

“Every success that I’ve had since then has shown me that anything is really possible,” he continued. “By not stopping myself, not limiting myself and just really going for it, I’ve learned a lot about myself and also had the opportunity to further the conversation on trans inclusion in sports.”

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He went on to call being the first trans man on a U.S. men’s national team “a dream come true.”

“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,” he added.

RELATED VIDEO: Transgender Duathlete Chris Mosier Poses Nude for ESPN’s Body Issue

Earlier this year, Mosier also made history as the first transgender athlete to appear in ESPN Magazine‘s annual Body Issue.

He earned his historic spot in 2015 with a sprint duathlon time of 01:02:45.48 at the national championships. He placed seventh in the male 35-39 group, and would go on to challenge previous International Olympic Committee policies which said transgender athletes were required to undergo genital reassignment surgery before playing.

The IOC’s adjusted policy now allows female-to-male transgender athletes compete immediately, while male-to-female transgender athletes must show a certain testosterone level for at least a year before playing.