WATCH: Mark Knowles pushing for no-ad scoring in singles on Second Serve

Andy Murray, usually among the hardest workers on tour, says he hasn't been training enough and needs to change that in the offseason.

The 35-year-old from Great Britain has been experiencing frequent cramps this season, including during his first-round defeat to Gilles Simon at the Rolex Paris Masters this week.

While he's now climbed back into the Top 50 for the first time since having hip resurfacing surgery, the three-time Grand Slam champion hasn't won more than two matches in a row since this summer when he reached the Stuttgart final on grass.

"It's nothing to do with my hip," said Murray, speaking to British newspapers. "I think just the reality is I need to work harder.

“I've not really done much since the US Open physically in the gym, or anything. I've done very, very little. And that's off the back of not doing a training period off the back of Wimbledon."


Calling it "really, really disappointing," he plans to improve his fitness going into next season.

"I will take that into the offseason, and make sure that it doesn't happen to start the year," said Murray, noting the effects of his lower ranking and playing a reduced schedule.

"I'm only averaging like one match a week. So the work that I do on the tennis court and on the practice court needs to be of a high enough intensity to make up for that."

Ivan Lendl, who coached him to three Grand Slam victories, rejoined the team starting at the Miami Open this season.

No changes to Murray's team have been announced.