Season 3: Episode 10 - The Yips

The Yips: The gang joins a gym, and there Barney runs into Rhonda, his mom's friend to whom he lost his virginity. He learns that the night in question was built on a lie: she only slept with him because his brother bribed her. His confidence destroyed, Barney tries to bounce back with a trip to the Victoria's Secret Fashion Show after-party, but gets "the yips," losing his ability to pick up on women. Realizing he has to make it with Rhonda for real so that he can return to his former self, Barney sets out on a mission. Meanwhile, Lily and Marshall struggle to deal with Marshall's overzealous trainer, and the gang discovers Ted's workout regimen isn't exactly as strenuous as their regimen.