woman in biphasic sleep
Sleep Health

What Is Biphasic Sleep? How To Start A Split Sleep Schedule

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    Last Updated
    April 4, 2022
    min read

    A third of all adults will experience occasional insomnia at some point in their lives. But for 10% of the adult population, insomnia can be a chronic condition with serious repercussions on their physical and mental health.

    Most experts recommend practicing good sleep hygiene to alleviate insomnia. However, in recent years, some researchers have suggested that the typical “eight hours a night” pattern of sleeping just doesn’t work for some people.

    Instead, they believe that a biphasic sleep pattern with segmented sleep periods could be more effective in getting more REM sleep and preventing sleep deprivation.

    Read on to find out what biphasic sleep actually is, and if it could be right for you.

    What Is Biphasic Sleep?

    Biphasic sleep, also known as segmented sleep or bimodal sleep, is one of three primary sleep patterns, along with monophasic sleep and polyphasic sleep. This sleeping pattern involves sleeping in two shifts or segments each day. For example, some biphasic sleepers will sleep five hours at night and then take a "siesta sleep" or afternoon nap for an hour and a half.

    There is enough evidence to show that biphasic sleep was quite common in medieval times, when people split their sleeps into “first sleeps” and “second sleeps”. Biphasic sleep is also common among various animals.

    Biphasic Sleep vs Monophasic Sleep

    Monophasic sleep is the pattern of sleep you’re likely already used to in which you sleep several hours at night and are awake for the rest of the day.

    According to Roger Ekirch, the monophasic sleeping pattern became popular during the Industrial Revolution, when people would spend long hours at work and have no opportunity to take a daytime nap. Around this time, people were also able to stay up longer thanks to electric lighting, so their circadian rhythms eventually changed. As a result, humans began to be able to fall into the deeper stages of the sleep cycle faster and later at night.

    Biphasic Sleep vs Polyphasic Sleep

    A polyphasic sleep schedule takes on several forms, like the Uberman sleep cycle or the Everyman pattern. Polyphasic sleeping is a segmented sleep pattern during which you’ll have more than the two periods of sleep that a biphasic sleep pattern allows. A polyphasic sleep pattern can be more difficult for many people to adjust to than a monophasic or biphasic sleep schedule.

    Usually, people who become polyphasic sleepers are those who aren't constricted by strict 9-to-5 jobs.

    The Advantages Of Biphasic Sleep

    So why would you want to shift to a biphasic sleeping pattern? For some, it can not only improve sleep quality but also one's overall happiness and productivity.

    Research shows that taking a midday nap can help preschoolers retain the information they absorbed before their nap. Research has shown similar effects on adults. One study from the University of California, Berkeley campus, found that adults who took a short afternoon nap had better cognitive function compared to non-nappers.

    Because biphasic sleep replicates the power of a short nap during the day, it comes with many of the same benefits that naps can provide, including lowering stress levels and boosting alertness.

    The Disadvantages Of Biphasic Sleep

    Biphasic sleep does require a daytime nap, so if you have a grueling work schedule without much room for schedule fluidity, it may not be the right pattern for you. Biphasic sleep can also be challenging if you’re the caregiver to children or pets who need to be supervised during the day.

    Some people may also find the transition to biphasic sleep a challenge. When you’ve gone years on your current sleep cycle, switching to a new one could disrupt your nighttime sleep or ability to nap, leaving you feeling fatigued.

    Finally, biphasic sleep long-term effects aren’t yet known because this sleep pattern is relatively new for researchers.

    Who Could Benefit From Biphasic Sleep?

    Biphasic sleep patterns may not work for everyone, just as monophasic or polyphasic sleep may not. But if you frequently hit a wall of midday sleepiness, this sleep schedule could be your best choice.

    Tips For Starting Biphasic Sleep

    Ready to try a segmented sleep pattern? These six tips should help you transition more easily.

    1. Choose Your Biphasic Sleep Pattern

    Sleep timing and length can vary depending on what sleep schedule works best for your lifestyle, energy levels, and day-to-day schedule. You can choose a schedule that works for you, but try to aim for the recommended total of seven to nine hours of sleep in 24 hours.

    Generally, most people who try biphasic sleep choose from one of two options:

    • Taking a short nap (usually a 20-minute nap will suffice) in the middle of the day and a long sleep of about six to seven hours
    • A long nap of about one to one and a half hours in the day plus a shorter sleep of about five to six hours at night

    2. Limit Your Exposure To Artificial Lighting

    According to research, exposure to artificial light at night can decrease levels of the sleep hormone melatonin. This can hinder us from getting enough restorative sleep. Studies have found that, when humans are less exposed to artificial light, their sleep naturally tunes to a segmented schedule.

    To have the best sleep periods possible, biphasic sleepers should try to limit their exposure to artificial light and blue light, especially outside of “awake” hours of the sun.

    3. Practice Good Sleep Hygiene

    Practicing sleep hygiene is as essential as practicing physical hygiene. Your body needs you to put routines in place that help you get to sleep faster and more soundly each night or before a nap.

    Some ways to practice good sleep hygiene include:

    • Limiting your caffeine intake
    • Creating a comfortable and dark sleeping environment in your bedroom
    • Maintaining a consistent bedtime routine that relaxes you, such as reading or drinking a cup of chamomile tea

    4. Choose The Right Mattress

    For those who aren’t used to daytime naps, falling asleep in the day can be hard, especially during the summer when it’s hot and humid. This is why it’s important to find a mattress that isn’t just comfortable but highly breathable as well.

    All Purple mattresses feature a two-inch breathable GelFlex™ Grid that cradles pressure points, keeps the body fully aligned, and lets air flow freely. The material itself, a high-quality Hyper-Elastic Polymer, doesn’t retain body heat, so you can have a cool sleep no matter the time of day.

    5. Consult With Your Doctor Or Physician

    Not everyone may be able to adjust to overhauling their sleep patterns as well as others. This is especially true for those with chronic conditions like depression and anxiety, which can be triggered by sleep changes. Make sure to consult your doctor before making any big changes.

    6. Track Your Results

    Biphasic sleep schedules aren’t for everyone, and there is no best biphasic sleep schedule that will work for everyone who tries it. Therefore, it’s necessary to evaluate how your schedule is working for you.

    Stick with it for a full week or two. Journal how you feel each day, including whether you feel tired, alert, moody, or energized, and how well you feel like you slept.

    What Kind Of Sleep Is Best For Me?

    Finding the right biphasic sleep schedule for your body and lifestyle is the most critical factor in being successful with this pattern of sleep. It may take a few weeks for you to settle into a biphasic sleeping groove that gets you through the day. However, once you find that perfect balance of day and night sleep, your body and mind will thank you.

    Frequently Asked Questions About Biphasic Sleep

    What is the most efficient sleep cycle?

    Each person is different, and so there is no such thing as the perfect sleep pattern.

    Is biphasic sleep healthy?

    Biphasic sleep can be healthy for people who have trouble sticking to the traditional monophasic sleep pattern.

    Are humans supposed to sleep twice a day?

    While there isn't enough evidence to show that biphasic sleep is our "natural sleep pattern", studies have shown that, in the past, people were accustomed to segmented sleeping.


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