When Mary Lou Retton started in gymnastics, there weren't very many women in the sport who looked like her.
"Back in my era, gymnasts were pixies, slender, very graceful little butterflies ... I wasn't," the 48-year-old former Olympian told CNBC. "I wasn't a pretty, little gymnast. I was a very powerful, explosive gymnast."
At the 1984 Olympics, Retton proved her critics wrong when she became the first American woman to win an individual all-around gold medal in the sport.
That year she took home five medals. She was subsequently named Sports Illustrated's Sportswoman of the Year.
For most of her life, people told her that she didn't have the "right body" for a gymnast, Retton said.
"When people see us standing on the podium and the medal stand with gold medals draped around your neck ... that's just the pinnacle of our success, but all of us, I'm sure — I know I did — have a story of struggle, a story of overcoming adversity to actually get there," she said.
"Well, I've always been different. I don't conform and here I am. I'm proud of that fact, that those walls have come down," she said.
Retton was able to push past her critics because of her love for the sport.
"It's being passionate about what you're doing and being in love with what you're doing, that's kind of the pot I drew from," she said. "That's not in my repertoire, to give up."
Retton's advice to young people is for them to not be afraid of committing to what they love.
"Don't find just a job. Find a career and just put everything into it. One hundred percent. Don't go half into anything," she said.