One-Legged Gymnast Adam Starr Shares Inspiring Story

Lifelong athlete Adam Starr, who lost one leg to cancer in 2009, has not let his amputation stop him from doing what he loves. INSIDE EDITION has his story.

21-year-old Adam Starr lost his leg to cancer, but that hasn't stopped him doing what he loves…gymnastics! He is inspiring people all over the world with his positive attitude.

He can do gravity-defying backflips and jump on the trampoline.

"I'm determined not to let my amputation get in the way of me doing the things I like to do," he tells INSIDE EDITION.

Starr has been a gymnast since he was 3 years old. In high school he was an accomplished diver.

But at 19 he was diagnosed with angiosarcoma, an aggressive, often fatal form of cancer. The only way doctors could save his life was to amputate his leg.

"It was tough news to hear but it was the best option," Starr says.

He refused to dwell on his misfortune; as soon as he was well enough, he was back in the gym.

"I remember standing on one leg one day balancing and kind of feeling like, 'Hey I wonder if I'm strong enough to do a backflip again?' " he recounts.

He recorded his first day back at the gym in Northfield, Minnesota, after losing his leg to show his friends and family what he could do.

The video quickly became a YouTube sensation earning Starr hundreds of thousands of admirers all over the globe.

And backflips are not all he can do.

Starr cycles with the help of a state of the art prosthetic leg and he can swim laps in the pool, as gracefully and effortlessly as an Olympic swimmer.

Our underwater camera captured him in action: a one-legged athlete, taking life's challenges in stride.