She's a world-renowned tennis player who's won numerous Grand Slam and Wimbledon titles in her 30-year career. Martina Navratilova talks with Gayle about her successful tennis career, her current work with the AARP and about embracing her sexuality.

Today, Martina serves as the health and fitness ambassador for the AARP, helping members become active and healthy. "It's a good fit because I am retired from tennis but I am not retired from life," she says. "For me it's an opportunity to reach 40 million people, hopefully helping them get more out of their life," she says.

Martina also talks with Gayle about struggling with her sexuality at an early age. Martina says she knew she was gay at the age of 19, after her first physical relationship with a woman. Martina says she is proud of who she has become and says her family was supportive in the end. "Living in the closet is terrible," she says. "I don't know one person [who came out] who wants to go back. Everybody who comes out is so happy they did and never wants to go back."

Today, Martina says she embraces her age, and is looking forward to what the future holds for her. "Age is just a number," Martina says. "How you act has nothing to do with your age. You define yourself, so don't let age define you."