MELBOURNE, Australia -- From technology to training, ice baths to oxygen pods, what to eat and even when to eat it, being a top tennis player has long meant more than just forehands and backhands.
And in the never-ending search to gain an edge, players are beginning to understand that something we all take for granted -- sleep -- could be the key to improving their performance, day in, day out.
Players have long appreciated that the quicker they recover, the better they're likely to train and play. Roger Federer once said he needs 11-12 hours of sleep per night, and you will often see players having afternoon naps during tournaments. But now they are looking at the science of sleep, especially useful when they are staying in hotels and apartments around the world.
Nick Littlehales is a sleep specialist who made his name working with Manchester United in the late 1990s and more recently with the Team Sky cycling team, which gave Britain its first Tour de France champion, Bradley Wiggins, in 2012.
Littlehales helps educate athletes about sleep and the "natural recovery process," working with them to figure out how much sleep they need while creating the ideal sleeping environment. Under his guidance, all Team Sky athletes brought their own pillows into the Olympic village at the 2012 London Games, part of their quest for marginal gains -- a belief that if you can improve a number of factors by 1 percent, it will make a significant overall improvement.
"When you look at it from an athlete's or player's point of view, they're always leaving a hotel or facility to go and perform," Littlehales said.
Karolina Pliskova, the Czech who reached the final at the US Open and is seeded fifth at the Australian Open, takes her pillow everywhere she goes.
"I have always travelled with my own pillow," Pliskova said. "My mum knitted it for me. It's kind of long and I need it. I don't need pills, I need this. If I don't have it, I am really nervous. I don't have any problems with sleeping, even on the plane. I just need my pillow."
Consistently replicating that home environment, when traveling for as many as 30 weeks a year, is far from easy for athletes, especially when factoring in different hotels and apartments, different beds, bed linens and air conditioning.
"You've got mental and physical demands, and your approach to mental and physical recovery has to have the same level of attention," Littlehales said.
"So when you're looking at performance levels, it's not reflecting your home like the hotel, but you want consistency of sleeping environment and sleeping product. So when you're looking at all the hotels and products you're using, you can sort of say, 'We'll use this hotel, not that one, because it ticks more boxes along this route.'"
When Littlehales works with athletes, he often goes into their homes and helps them set the right temperature and environment. Canadian Milos Raonic, seeded third at the Australian Open, told The Age newspaper that he had figured out his optimum sleeping temperature, 19.4444 degrees Celsius. "I'm a big guy," he said. "I need a little bit more sleep to recover, so if I lose sleep during tournaments or even before tournaments for one or two nights that doesn't come back just through one long nap or so forth. So I'm trying to have as few hiccups in that regimen as possible."
The United States Tennis Association, Lawn Tennis Association in Britain and Tennis Australia all have researched the importance of sleep. The LTA has sleep pods at the National Tennis Centre in London. But on the road, players are left to their own devices, which presents obvious problems.
"Individual athletes in their homes, some go completely crazy and bring in all sorts of things that are not transferable when they're travelling," Littlehales said. "That's one of the biggest mistakes. They might go out and buy a £3,500 Siberian goose down, 13.5 tog mega duvet, and then they're sleeping under some microfiber thing that's rattled through 60 washes every five minutes in a Hilton Hotel. The mattress in there is designed for people who are 200 kilograms, so it lasts forever and no one breaks it. It's not for you at 60 kilograms."
Littlehales says everyone has his or her own chronotype, which defines how much sleep a person really needs. He also adheres to the theory that people have 90-minute sleep patterns. So athletes who want to wake up 7:30 a.m. should count back in 90-minute segments to, say, 10:30 p.m. to start sleeping. If they miss that bedtime, they would be better off waiting until the start of the next 90-minute cycle in order to get the deepest sleep possible.
Top-ranked Andy Murray said there's one thing he tries to keep consistent in his sleep habits. "I always sleep with the air conditioning on," he said. "I know some people hate that. They say it makes them sick, gives them a sore throat. But I always sleep with the air conditioning on, then get under the covers. I sleep better that way.
"Sometimes I wear compression leggings if I've had a long match. Normally, during these events, I try to sleep as much as possible. I try and have a nap during the day on the off days because that also helps your recovery."
Some players don't do anything special for sleep. US Open champion Stan Wawrinka said that sleeping is not as simple as it was when he was young but that he had no problems. "I don't need something to feel good," he said. "I just try to do the right schedule, practice at the right time, eat what I need to ... and that stuff, but nothing special."
Belinda Bencic of Switzerland, who is making her way back after injury, said she can sleep anywhere. "That's a big advantage because a lot of people have these kind of problems," she said.
Littlehales said there is still more research to be done to quantify exactly how much difference proper sleep makes, though it almost always improves performance. "When I work with somebody, what comes out straight away is their confidence," he said. "They stop worrying about it; they take control of it. They feel far more positive about what they're doing, whether they're sleeping or not, to cope with what's coming for them."