Matt Iseman has a cool job—a really cool job.

For eight seasons, he's been one of the hosts of one of the most exciting shows on television: American Ninja Warrior.

But hosting a hit TV show was far from something that came overnight, or came easily to Iseman. In fact, he went through a complete career 360 to get there.

Before show business, Iseman was a practicing doctor, and it wasn't until an experience working one day in an ICU unit that he realized he wasn't in the right place. Shortly thereafter, he decided to move out to Los Angeles to pursue comedy. He gave himself two years—and sure enough, he made it happen.

In our interview above, Iseman opens up about the details of his career transition, dishes out advice for ambitious young professionals, and shares a fitness assessment of what seperates a mere Ninja Warrior competitor from a winner.

Tune into American Ninja Warrior on Mondays at 8 p.m. / 7 p.m. Central on NBC. Follow Matt Iseman on Instagram (@MattIseman) and Twitter (@MattIseman).