Sleeping three times a day (polyphasic sleep) isn't inherently good or bad; it depends on the total hours and your body, but for most adults needing 7+ hours, it risks sleep deprivation, affecting focus, mood, and health unless it's a short, planned pattern (like naps) fitting your total sleep need without negative effects like fatigue or disrupted rhythms, which indicate it's not working. While it's a popular idea to boost productivity, scientific evidence doesn't support it, and inconsistent, short sleep often harms health more than it helps.
But for the most part, studies suggest biphasic sleep patterns are relatively harmless. So long as you're still getting approximately seven to nine hours of sleep a night, most research suggests it's fine if that sleep happens in two sessions.
You can sleep for six hours and take a nap, but sleeping for longer at night is better as sleep works best when it's uninterrupted. However, if you can't get enough sleep at night, sleeping for six hours and taking a nap can help you catch up on lost sleep and boost your energy levels.
After 3 days of sleep restriction of 4–6 hours, some of the subjects exhibited the same decreased reaction times and cognitive dysfunction as displayed in subjects that had been observed in testing total sleep deprivation.
The 3-3-3 rule for sleep is a technique to help manage anxiety and improve sleep quality. It involves focusing on three things you can see, three things you can hear, and moving three parts of your body.
The 3-2-1 bedtime method is a simple sleep hygiene strategy: stop eating 3 hours before bed, stop working 2 hours before bed, and stop using screens (phones, tablets, TVs) 1 hour before sleep, helping your body transition to rest by reducing stimulants and digestive load for better sleep quality. A more detailed version adds 10 hours (no caffeine) and 0 (no snoozing) for a 10-3-2-1-0 rule.
The koala is famous for sleeping around 20-22 hours a day, which is about 90% of the day, due to their low-energy diet of eucalyptus leaves that requires extensive digestion. Other extremely sleepy animals include the sloth (up to 20 hours) and the brown bat (around 20 hours), with some snakes like the ball python also sleeping up to 23 hours daily.
Signs of poor core sleep (deep, restorative sleep) include waking up foggy, daytime fatigue/energy crashes, poor concentration, irritability, frequent illness, memory issues, and mood swings, indicating your brain and body aren't fully repairing and consolidating memories. You might also experience increased sugar cravings, slow muscle recovery, and a weakened immune system.
Musk goes to bed around 3 a.m. and gets about 6 hours of sleep every night. Although he's not getting eight hours a night, Musk has upped his sleeping schedule from being nearly nonexistent in the past. In May 2023, Musk told CNBC that he's no longer pulling all-nighters.
With total sleep opportunity at 8 h—the minimum recommended, we found that a split sleep schedule with 6.5-h nocturnal sleep and a 1.5-h nap achieved similar performance in basic cognitive tasks, subjective alertness, and mood as the nocturnal sleep only schedule.
Yes, the Navy SEAL sleep trick (an 8-minute power nap with elevated legs) is a real technique for quick rest, popularized by former SEAL Jocko Willink, that helps improve alertness and reduce fatigue, though its effectiveness depends on individual relaxation skills and it's not a substitute for full nighttime sleep. The method involves lying down, elevating your feet above your heart (on a chair or couch), relaxing facial muscles, dropping shoulders, and clearing your mind for about 8-10 minutes to promote relaxation and blood flow, preventing grogginess.
It recharges us with new energy
Your tired eyes need to close for a few hours while your brain “cleans itself up” and your body produces many new cells!
For most healthy adults, guidelines suggest at least seven hours of slumber. But these are general recommendations and not strict rules. "Some people need less than seven hours, while others might need more," says Eric Zhou with the Division of Sleep Medicine at Harvard Medical School.
Among the most rested countries surveyed by Sleep Cycle, an app that tracks how much shuteye people are getting, New Zealand comes top with the average Kiwi clocking up in excess of 7.5 hours per night. Finland, the Netherlands, Australia, the UK and Belgium all rank highly for sleep, too, with Ireland close behind.
Editor's note: Kleine-Levin Syndrome mostly affects teen boys, causing them to sleep up to 20 hours a day during episodes that can last weeks. It's rare, possibly affecting one person in a million, with a higher incidence among Jewish people. There is no definitive cause or treatment.
Our circadian rhythm functions by light and dark cycles and therefore an ideal sleep time is 10pm – 6am give or take ½ an hour either way so a full 8 hours of sleep is achieved each night. Even if you are retired or not working, this is an essential component of good sleeping habits.
In his piece, he revealed that through his years of research, he's found that rumination is the biggest thing that causes poor sleep. He says that being worried about something at night has affected his own ability to fall asleep.
Go to bed and get up at the same time every day, including weekends. Being consistent reinforces your body's sleep-wake cycle. If you don't fall asleep within about 20 minutes of going to bed, leave your bedroom and do something relaxing. Read or listen to soothing music.
Albert Einstein is said to have slept 10 hours per night, plus regular daytime naps. Other great achievers, inventors, and thinkers – such as Nikola Tesla, Thomas Jefferson, Thomas Edison, Winston Churchill, Leonardo da Vinci, and Sir Isaac Newton – are said to have slept between two and four hours per day.
Based on available studies, “We have solid evidence that exercise does, in fact, help you fall asleep more quickly and improves sleep quality,” says Charlene Gamaldo, M.D. , medical director of Johns Hopkins Center for Sleep at Howard County General Hospital.