Roger Federer training half-days to lighten workload

Federer, who partnered with Belinda Bencic to win the Hopman Cup for Switzerland, says he now needs a different approach to fitness and practicing in his mid-30s than at the beginning of his career.

''When you're younger, you have to be able to put in the hours just to tell yourself, ‘I can stay on the court for four hours, do training 10 days straight,’ '' he said in a courtside interview during Hopman Cup. "You have to prove to yourself you can do it. It's a bit more of a mental thing, in my opinion.

"Of course, your game needs it—your game needs a lot of tennis, you need a lot of fitness so you don't get hurt as often."

Now, Federer jokingly questioned whether he can still be considered a full-time player, just practicing for half a day on a regular basis.

"And then as you get older... it becomes more quality-orientated, and not so much quantity, because quantity hurts the body. I've played almost 1,500 matches in my career so you have to be careful of that," he said.

"I work in the mornings and have the [rest of the day] off, or the other way around."

That helps the rest of his schedule too, Federer added. The 19-time Grand Slam champion and his wife, Mirka, have four children.

"It's good to be a dad, it's good to be a husband, it's good to be a tennis player," Federer said. ''So I've got the best of both worlds.''

The world No. 2's playing style has also shifted in recent years, with more offensive play reducing wear and tear and more fully using his varied array of shots. "I can't be playing long rallies 5 meters behind the baseline," he said. "I mean, I could, but the other guys are better at it."

Federer won all of his singles matches at the Hopman Cup team competition.