Roger Federer sleeps 12 hours a day, which is helping his longevity

How much sleep does an elite athlete need? Or any athlete for that matter? Well, if you ask one of the greatest tennis players of all time, you might get a number at the higher end of the spectrum. Indeed, Roger Federer once said:

"If I don't sleep 11 to 12 hours per day, it’s not right. If I don't have that amount of sleep, I hurt myself."

Does this change our preconceived notion that more than 8 to 9 hours of sleep is too much and harmful in the long run? Aren't all hard-working athletes supposed to wake up at the break of dawn and go about their day with ascetic discipline?

Sleep scientists think not; they actually give a thumbs up to Roger Federer's sleep routine. A number of studies have shown that sportspersons actually need more sleep than the average Joe because recovery is crucial to them performing at peak levels.

Since professional athletes exert themselves so strenuously on an average day, their body suffers more than the normal share of wear and turn - leading to chronic inflammation. And sleeping more than eight hours goes a long way towards countering that inflammation, and helping the individual recover fully for the next day.

Roger Federer is believed to sleep for 10 hours at night with a two-hour daytime nap thrown in. But even with half of each day of his life spent in blissful slumber, the Swiss maestro has managed to win a record 20 Grand Slams. And he continues to be one of the best in the business in a highly-demanding sport even at the age of 38.

Maybe those hours spent regrouping have something to do with his awe-inspiring longevity?

Many other great athletes sleep a lot, in addition to Roger Federer

Usain Bolt

Another certified champion and the current holder world record holder in the 100m and 200m sprints, Usain Bolt also sleeps for about 10 hours a day. The former sprinter, often considered the greatest athlete of his time, also threw in naps during the day to keep himself energised.

"Sleep is extremely important to me -- I need to rest and recover in order for the training I do to be absorbed by my body," the Olympic champion once said.

LeBron James, one of the greatest athletes the game of basketball has ever produced, reportedly needs 12 hours of sleep to keep performing at the elite level. A four-time NBA MVP and three-time winner of the championship, LeBron is one of the fittest players on the court. Maybe he is just getting better sleep than his rivals!

Then there's the case of an athlete who took his sleep regimen to another level. Literally.

The most decorated Olympian of all time, Michael Phelps, simulated sleeping at an altitude of 8,500-9,000 feet. The benefits are obvious. With less oxygen, the body is made to work harder to supply energy to the muscles, thus enhancing performance at sea level.

It must have worked, because Phelps won 28 Olympic medals before hanging up his swimming trunks and taking some well-deserved rest.

Michael Phelps can now put his feet up after 28 Olympic medals

Returning to tennis, it seems Roger Federer's elite colleague, Andy Murray, was sleeping for 12 hours a day during his winning Wimbledon run in 2013. The Scotsman became the first British tennis player in 77 years to win the crown.

Maria Sharapova has also been quoted to love her sleep.

At the opposite end of the spectrum is Rafael Nadal, one of the busiest players on court and Roger Federer's long-time rival. Nadal is not a fan of excessive sleeping, but even he ensures he gets those eight hours in during competition.

Only time will tell whether the demands of his highly-physical game will wear him down, or if he is able to match Roger Federer's longevity at the biggest stage.

Diet, exercise and training have always been considered the cornerstones to an athlete's success. But sleep might well be the fourth pillar required to make the edifice stand.

Roger Federer's is a case in point. Recovery is just as crucial to performance as the other three factors mentioned above, and Federer's longevity in tennis is proof of that.

As Roger Federer continues to pursue excellence in the twilight of his career, he would do well to ensure he is getting his sleep right as well.