Roger Federer says players have to re-examine their playing schedules as they get into their 30s, and avoid playing with injuries.
Both No. 1 Andy Murray and No. 4 Novak Djokovic had injury-affected exits at Wimbledon, having just recently turned 30 themselves. Murray had a hip problem, while Djokovic retired with an elbow injury he says has affected him for a while.
"It's normal," said Federer. "Once you hit 30, you've got to look back and think of how much tennis have I played, how much rest did I give my body over the years. How much training have I done? Did I do enough? Did I overdo it or not enough? It's always calibrating the whole thing."
But that doesn't necessarily mean taking an extended break like he did. Federer did not play for much of 2016 because of a knee injury, and has returned to win four of the first six tournaments he has played, including the Australian Open.
"For me it worked out. Doesn't mean it's going to work out for everybody," he said. "You just want to take that decision early enough or see it coming and anticipate.
"The problem is you can only play with a certain injury for a certain amount of time, because what you don't want happening is that it becomes chronic ... Even a surgery can't help you that much anymore."
Federer, 35, is the oldest man in the Top 10 of the ATP rankings.
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