Jen Selter is the self-made social media sensation of the fitness world.

With more than 2.6 million followers on Instagram, more than 653,000 likes on Facebook, and 360,000 followers on Twitter, the 20-year-old is becoming an Internet phenomenon for the fitness poses that highlight her body, particularly her toned derriere.

In an interview with "Good Morning America," Selter revealed that she's never had a trainer in her life.

"I would just follow the trainers and when they were training someone I was like, 'oh, what does that do?'" she said.

She's been seen around New York City performing her signature move, Seltering, in which she poses on hands and feet and sticks out her shapely rear.

Selter said it all started out innocently enough.

"If I was wearing a cute outfit I was like, why not take a selfie?" she said.

One photo in particular started her rise to fame.

"I took one of, like a side of my butt in yoga pants and that picture went viral," she said.

Some of the exercises that make her workouts unique include walking dumbbell lunges, twisted plated squats and donkey kicks - or fire hydrants.

As for what she eats to maintain such an enviable figure?

Well, she eats carbs. And dark chocolate is her guilty pleasure. She also loves cereal, and will eat ice cream with her cheat meal on Sunday.