Woman's Dramatic 280-Pound Weight Loss: 'I Have My Life Back'

— -- At 457 pounds, Rhonda Martin could barely walk. Even breathing was a chore. She certainly never imagined that one day she would look like she does now— nearly 300 pounds lighter.

“I was just existing,” Martin, of El Cajon, California, told ABC News. "I had no social interaction with people. My life was very limited.”

Desperate to lose weight, she tried countless fad diets, even weight loss pills, but she always gained it right back.

“I knew that if I didn’t get my blood pressure under control and get the weight loss off, there was a great risk of me dying soon,” she explained.

Fearful for her life, she ditched her old, unhealthy eating habits and started drinking protein shakes.

“It’s only two shakes a day, and then the other three meals that I’d have would be just regular food, so I wasn’t limiting myself to the shakes,” said Martin.

She began counting her calories, drinking eight glasses of water a day and using a pedometer to track her steps, pushing herself to walk 100 more steps each day.

“By setting these tiny, mini goals along the way, it kept me focused,” she recalled.

And when walking wasn’t enough, Martin began riding an electric bike.

“It was amazing for a woman of my size to be able to get on a bike and be able to move as freely as I was able to move,” she said.

Tracking her two-year weight loss journey with her 15,000 devoted Facebook followers, Martin went from 457 pounds in February 2012 to about 180 pounds now, a dramatic 280-pound weight loss.

“For me to be under 200 pounds, I never thought that would be possible,” she said.

But her personal journey didn’t end there.

“I did the Spring Sprint Triathlon,” said Martin. “After I finished the race, I went home and I signed up for my next one.”

Since then, the 43-year-old has completed three half-marathons and four sprint triathlons, and she is now training for a full Ironman.

“I have my life back,” she said. “Before, I was just existing and now I am living my life and I’m living it the way I want to live it.”