Tiger Woods says he can't train all-out like he did in his 20s. Kobe Bryant is playing his fewest minutes per game since his second season in the NBA and is practicing even less.

Then there's Roger Federer.

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The 33-year-old Swiss superstar, the No. 2 tennis player in the world, played 85 matches in 2013, the most matches he's had since 2006, according to Perth Now. Federer finished 2014 with a 73-12 match record; he was 92-5 in 2006.

If he wins the 2015 Australian Open, which takes place next month, he would be the oldest man in more than 40 years to win the event.

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But Perth Now quoted Federer as saying that he would reassess his competition schedule after the Australian Open - to determine if he should play more events.

"People are always going to talk me down ... 'He is old and not so fit anymore', but I feel I have never cramped on court, I am one of the fittest guys on the tour - I back myself (to win),'' Federer said in India last week.

"This year I was close. Novak (Djokovic) played well at Wimbledon (beating Federer in an epic, five-set match) and (Marin) Cilic was on fire at the U.S. Open (in their semifinal). The others, I really created opportunities."

Zeenews.india.com illustrates Federer's point about the doubt about him as he looks toward his 34th birthday in August.

In handicapping the men's tennis competition in 2015, zeenews.india.com says, "With Federer in sight of his 34th birthday in 2015 and with continuing doubts over the fitness of Rafael Nadal, it is Djokovic who will be the man to beat in the new year."

Still, it's hard to argue with Federer's strategy as he takes aim at the No. 1 ranking that Novak Djokovic currently occupies. He started 2014 as the No. 8 player in the worlds as a back injury slowed him in 2013 to 63 matches.

He split his six matches against Djokovic in 2014, having to withdraw in the ATP World Tour finals with a back injury. But in their previous match, it was Federer who beat Djokovic in just over an hour and a half in the semifinals of the Shanghai Masters.