Science says you can take a guilt-free afternoon nap. No, really. Getting all of your sleep in a single stretch is the most common sleep cycle, but it may be beneficial to split your sleep for some. There could be cognitive benefits to a quick, 15- to 20-minute couch nap when you hit your 3 p.m. slump.
There are different types of sleep cycles to consider if you have an unconventional schedule or don't need a lot of sleep. Some cycles result in as little as two to four hours of sleep throughout a 24-hour period. You may want to consider the possible downsides of cutting down on your sleep before you drastically change your schedule.
What is the standard sleep cycle?
The standard sleep schedule is one long slumber, usually at night. This is also called the monophasic sleep cycle. Getting your rest all at once gives your body enough time to go through the various sleep cycles. This approach allows your body to complete the full range of sleep stages, including REM -- also called stage 4, or rapid eye movement.
Monophasic
In modern times, monophasic sleep is the standard cycle. Many experts recommend this sleep schedule because it best aligns with your body's circadian rhythm, which is largely guided by light and dark. This means your brain signals you to wake up when the sun comes up and begins to release melatonin and make you sleepy when it gets dark out. Sleeping in one long stretch also makes it easier for many people to achieve the recommended seven to nine hours of sleep per day as an adult.
Your body goes through four stages of sleep each night. Annie Miller, licensed psychotherapist and sleep expert told CNET, "NREM sleep includes three stages, with Stage 3 (previously known as Stage 4) being the deep restorative phase. Stage 3 sleep is crucial for bodily repair, muscle growth and cognitive functions like memory consolidation. This stage typically begins about 90 minutes into the sleep cycle, though this timing can vary." She continued, "Monophasic sleep, which involves a single, uninterrupted sleep period, increases the likelihood of experiencing sufficient amounts of deep sleep, allowing your body to progress through all sleep stages."
What are alternative sleep cycles?
Getting all of your sleep at once is a relatively modern convention. If you always need a nap at 3 p.m. or you prefer to sleep in three-hour increments throughout the day, you may be tapping into a sleep cycle with a historic history. Limiting your sleep is not for everyone. Miller added, "While these alternative sleep cycles may fit certain lifestyles, insufficient total sleep may lead to negative outcomes for some."
Biphasic
Biphasic sleep (sometimes called bimodal sleep) refers to a slumber schedule that is broken up into two parts. This could mean sleeping at night and taking a short nap or 60- to 90-minute siesta in the middle of the day, or breaking up your nightly sleep into two parts. Miller clarified, "This can mean having a longer sleep period at night followed by a shorter nap during the day, or splitting your sleep into two substantial segments within a 24-hour period."
The first sleep/second sleep schedule was common prior to modern lighting and machinery. People would often sleep once for a few hours beginning at about 9 p.m. and then wake up at midnight for a few hours before sleeping again for a larger block of time.
The benefits of biphasic sleep include cognitive health. If you often experience fatigue and brain fog in the middle of the day, even a short nap can boost cognitive function for the rest of the day. Breaking up sleep into two phases may also better accommodate complicated schedules or morning people who wake before dawn. For people who work unconventional hours or observe specific prayer hours, biphasic sleep can make a lot of sense. Miller added, "However, the effectiveness of this sleep pattern can vary depending on personal needs and lifestyle."
Everyman
If you can get by on less sleep than the average person, the Everyman cycle may work for you. This method requires three solid hours of rest at night and three 20-minute naps throughout the day. You'll get a total of four hours of sleep per day. While this is efficient, Cleveland Clinic warns that consistently falling short of seven to eight hours of sleep could result in sleep deprivation.
Some people can run on fewer hours of sleep. Miller told CNET that the Everman cycle may work for a group of people called "short sleepers." She stated, "Short sleepers naturally function well on less than six hours of sleep per night. Short sleepers are rare and usually have a genetic predisposition that allows them to maintain cognitive and physical health with reduced sleep."
The Everyman schedule could also be a good short-term option for people who are working long hours or have a new baby. Supplementing a short nighttime sleep with multiple naps could keep you more alert and rested until you can resume a more regular schedule. Although, daytime sleep can negatively affect your ability to fall asleep at night for some.
Dymaxion
This sleep cycle gives you just two hours of sleep per day. Created by architect and inventor Richard Buckminster Fuller, this cycle mirrors Fuller's work methodology, which was to generate "maximal output from minimal energetic input." The Dymaxion sleep cycle involves getting 30 minutes of sleep every six hours.
This type of sleep can accommodate long travel schedules or other extreme situations, it also falls far short of recommended sleep hours for adults.
Uberman
The Uberman cycle was inspired by the Dymaxion model and results in the same amount of sleep, just on a slightly different schedule. This sleep schedule involves six 20-minute naps per day or one nap every four hours. The creator, Marie Straver, said she suffered from insomnia in college, and this sleep schedule helped her get enough rest to be productive throughout the day.
The Uberman schedule may be good for people who have insomnia or need a short-term solution, but it may not give you enough REM or deep sleep. "The success of this is anecdotal and if you are struggling with insomnia, this would not be an effective way to treat insomnia. Sleeping during the day can lead to further insomnia by reducing your ability to fall asleep at night," Miller stated.
Drawbacks of biphasic and polyphasic sleep cycles
A 2022 literature review published in the Journal of Sleep Health found no provable benefits to polyphasic sleep cycles. The researchers concluded that current evidence suggests there may be serious risks. The sleep deprivation caused by polyphasic schedules could lead to a variety of negative outcomes related to mental health, physical health and cognitive performance.
"While chronic sleep deprivation can have adverse effects, there are some nuanced considerations. For instance, higher sleep drive due to partial sleep deprivation can reduce insomnia and increase restorative deep sleep," warned Miller. "Additionally, controlled sleep deprivation has been explored as a treatment for depression in certain clinical settings. That said, for most people, consistent, ongoing sleep deprivation is likely to be detrimental, impacting overall health and daily functioning."
Notably, these outcomes are related to lack of sleep. If you choose a biphasic or polyphasic sleep schedule that keeps you close to the recommended minimum sleep for adults, you may not experience any negative outcomes.