Andy Murray, Rafael Nadal and Novak Djokovic have all suffered lengthy injury absences over the last 12 months, leading some to suggest that five-set matches at grand slams are too punishing.
"It's really becoming so taxing that I believe one day we will have two out of three sets in the grand slams, otherwise they're going to be taking people out on stretchers," the 18-time grand slam champion said.
"We have always had issues with injuries, but this year it came to light more so when the top guys are hurt. Rafael Nadal's had issues, he was out for about eight months. Now Andy Murray has missed the French Open because of a bad back and Novak Djokovic had issues as well with his ankle.
"We're playing on hard surfaces most of the year, not clay. We used to play with wood and gut, now they play with metal or some kind of synthetic racket. They put a lot more hours in and everybody hits the ball harder, you have to run harder. Plus the courts are slower so the rallies take longer. This has to take its toll on the body."
On the first day of Wimbledon, Navratilova told laureus.com: "You play a long match and it takes you months to recover, because it's like running a marathon in sprints, but then sometimes you have to go out and play a match the next day or two days later."
Navratilova's stance is likely to irk traditionalists within the game, but the American points out that changes have been made to the format of the game in the past.
She added: "We have changed the scoring system, where it shortens some games at least. But we didn't have tie-breaks until the '70s in tennis, so that we used to have 14, 12, 24, 22-game sets all the time. Now imagine if we didn't have tie-breaks and playing three out of five - good luck! So, yes we've changed the rules in tennis and this is another one that could happen."