The tennis legend lost out in the final of the show to Joe Swash, while actor George Takei finished third.
Navratilova told hosts Ant and Dec that she enjoyed her time in the jungle, saying: "I'm feeling just fab. I'm happy for Joe. It was a treat."
She called the experience "slow, but then action-packed", saying: "It was rough. I've never been challenged at such a sustained level."
Martina also revealed that she learned a lot about herself during her jungle stay. "I found out that I can adjust very well to a situation and that I can go into a room full of people and I've never met before and make friends," she said.
When asked about David Van Day, she told Ant and Dec that she felt he had a gameplan from the beginning. "He has a different persona for the camera. He just didn't do his share. That's what annoyed me."