For busy, successful people, sleep is a precious commodity — rare and treasured.
So when it comes to getting a solid night of shut-eye, some do everything they can to not let insomnia, pressure at work, or snoring spouses get in the way — even if that means creating a weird nightly routine or napping to get through the day.
Here's a look at the most bizarre sleeping habits of 13 highly successful people.
This is an updated article originally written by Vivian Giang.
Cruise's snores are apparently so bad, he sleeps in a sound-proof "snoratorium." Once a nursery, Cruise converted the small room at the back of his house to a sound-proof space where he can snore in peace.
"Whoever uses the snoring room cannot be heard outside the locked door," an alleged visitor to the actor's house told the Daily Mail. "It's very small, comfortable, and dark."
Winston Churchill took a two-hour nap every day.
Every day at 5 p.m., the prime minister would drink a weak whiskey and soda before taking a two-hour nap. Churchill said this short "siesta" allowed him to get one and a half day's worth of work out done every 24 hours.
Churchill would often work through the night and became known as quite the night owl. Due to his irregular sleep schedule, he was said to hold War Cabinet meetings in his bath.
Mariah Carey surrounds her bed with 20 humidifiers and needs 15 hours of shut-eye per night.
"I've got to sleep 15 hours to sing the way I want to," Carey told Interview magazine in 2007.
The singer also admitted to sleeping with 20 humidifiers around her bed, which soothe sore throats and add moisture to dry air. "Basically, it's like sleeping in a steam room," she said.
All of Stephen King's pillows are pointed in a certain direction.
According to Lisa Rogak's book "Haunted Heart: The Life and Times of Stephen King," the science fiction writer has an odd nighttime ritual.
"I brush my teeth, I wash my hands. Why would anybody wash their hands before they go to bed? I don’t know," he says. "And the pillows are supposed to be pointed a certain way. The open side of the pillowcase is supposed to be pointed in toward the other side of the bed. I don’t know why."
Leonardo da Vinci's sleep schedule included 20-minute naps every four hours.
Da Vinci followed an extreme form of a polyphasic sleep schedule called the Uberman sleep cycle, which consists of 20-minute naps every four hours.
This unconventional sleep cycle may have given the artist/inventor/scientist more awake time during his days, but could have also made it difficult for him to work on long-term projects.
Martha Stewart only sleeps four hours per night.
Stewart's hard work is evident in her success, but other parts of her life have suffered, including her sleep schedule. She gets up hours before her crew arrives at 6:30 a.m. to cook breakfast for a host of pets — including horses, donkeys, and over 200 chickens.
Stewart also stays up late reading or watching late-night TV. "It's an exhausting lifestyle, and I always say sleep can go," she told WebMD. "It's not important to me right now."
Eminem puts tin foil on his windows to keep out the light.
Most people put dark shades on their windows to keep their rooms dark, but rapper Eminem takes it to another level by wrapping tin foil around his windows to get better quality sleep.
He also listens to white noise throughout the night, which he claims helps him sleep better when traveling between different time zones.
Novelist Emily Brontë walked around in circles until she fell asleep.
The 19th century novelist and poet suffered from insomnia, and would walk around her dining room table until she felt tired enough to fall asleep.
Charles Dickens slept facing north to improve his creativity.
Dickens, who reportedly suffered from insomnia, always kept a navigation compass with him to ensure that he wrote and slept facing north. The writer believed this quirky practice improved his creativity.
Marissa Mayer catches up on sleep during weeklong vacations every four months.
Yahoo's CEO is known to be a workaholic, sometimes clocking as many as 130 hours in a week, which doesn't leave her much time for sleep. To catch up, she recharges by taking weeklong vacations every four months.
Michael Phelps sleeps in a chamber with air comparable to 8,500 to 9,000 feet.
By placing his bedroom at a high altitude, Phelps decreases the amount of oxygen available, which forces his body to work harder to produce more red blood cells and deliver oxygen to his muscles. It also helps Phelps increase his performance endurance and prepare himself for competitions at high elevations.
"Once I'm already in my room I still have to open a door to get into my bed," Phelps said on CBS News program "60 Minutes" in 2012. "It's just like a giant box. It's like 'boy and the bubble.'"
Inventor Nikola Tesla never slept for more than two hours a day.
Tesla got more out of the day with his limited sleep schedule. Like Da Vinci, Telsa also followed the Uberman sleep cycle and claimed to never sleep for more than two hours a day. He once reportedly worked for 84 hours straight in a lab without any rest.
"I do not think there is any thrill that can go through the human heart like that felt by the inventor as he sees some creation of the brain unfolding to success ... Such emotions make a man forget food, sleep, friends, love, everything," he said.
Lyndon B. Johnson divided his day into two shifts.
The president split his day into two parts in order to get more done. He usually woke up around 6:30 or 7 a.m. and worked until 2 p.m. After a quick bout of exercise, Johnson would crawl back into bed for a 30-minute nap, getting up around 4 p.m. and working into the early morning.
Johnson reportedly picked up his napping routine from his predecessor John F. Kennedy, who also broke up his day into shifts.
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