The 16-times grand slam champion will celebrate his 31st birthday in August. Though he has not clinched a grand slam title since the 2010 Australian Open, he has won five of his last seven tournaments.

"I've been feeling good for some time now," a relaxed and comfortably dressed Federer told reporters at the Indian Wells Tennis Garden while preparing for his first match in the ATP Tour event.

"I am playing well at the moment, for many months now, and it was nice winning a tournament again outdoors, not that I needed it but it's a great tournament to win in Dubai."

Federer beat British world number four Andy Murray 7-5 6-4 to win the Dubai Championships on Saturday, his 10th ATP World Tour title since the 2010 Australian Open.

"My body has been holding up well," the Swiss added. "I don't think I've over-played, to be honest, but I've just played enough. I have to be careful that I do everything right not to get injured. I have been feeling really good out there.

"It's nice going out on the court, playing the big points and knowing exactly what you want to do, what you can do and what you can't do. Sometimes when you don't play enough, you forget all those things and it's a bit of a blur."

Federer, who won three consecutive titles at Indian Wells from 2004-06, said he gradually stopped playing other sports as he got older to stay injury-free for tennis.

ENERGY LEVEL

"I've done my fair share of mistakes early on and as time goes by you just don't have the same energy level anymore," added the Swiss, who will play either Russian Dmitry Tursunov or American wildcard Denis Kudla in the second round at Indian Wells after enjoying a first-round bye.

"Through skiing and playing squash and playing tennis and soccer, you are like 'I can't believe I just did that because my knee hurts now and I can't move no more'. So you start cutting back a bit and you start having other interests that are maybe not so brutal on the body.

"And eventually it's the time I am in right now, I just don't do any other sports any more than tennis. I just follow them and watch them.

"I think every player goes through a phase like that where you realize it's just too important to your career and you don't want to get injured doing something stupid."

Fededer, seeded third at Indian Wells for the first Masters Series event of the year, is scheduled to meet twice champion Rafa Nadal of Spain in the semi-finals.

(Reporting by Mark Lamport-Stokes; Editing by Ian Ransom)

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