Do you remember your early years back in kindergarten when taking afternoon naps wasn’t only encouraged, but was a mandatory part of your school schedule? Back then you may not have understood why, but there was a reason why. Those childhood naps were a representation of a sleep pattern known as biphasic sleep (alternatively referred to as segmented sleep, diphasic sleep, divided sleep, siesta sleep or bimodal sleep) a pattern that provided you a lot of benefits.
Research conducted in recent years suggests that sleeping two times within a 24-hour period may facilitate alertness, productivity, cognitive function, and boost energy levels.
However, as we grow up and reach adulthood, a majority of us are trained to or end up compressing all our sleep time into a single overnight block.
As a result, a large number of people today are monophasic sleepers, which means that we only sleep once within a 24-hour period, and usually during the night.
While monophasic sleeping may be the norm amongst ‘grown-ups,’ more studies indicate that we might actually be better off returning to the good old biphasic patterns we were accustomed to during our childhood.
Here is a look at what biphasic sleep is. Why there is historical precedent for readopting the sleep pattern. How it could be beneficial to you, and how to experiment with it by transforming your sleeping style to favor the pattern.
Understanding Biphasic Sleep
You might not remember yourself as an infant, but you know that you used to nap a lot as a tot.
Babies often never sleep through the night, and their sleep is generally divided up into several sessions of sleep throughout the day.
And the same applies to every other human who exists and ever existed on this earth. This sleep pattern represents something known as the polyphasic sleep.
As an infant grows into toddlerhood, they start cutting back on the amount of time they nap during the day until they find themselves sleeping for longer chunks of time at night. And then only snoozing once during the day which represents a variation of what we now know as biphasic sleep.
While the term ‘Biphasic’ may sound a bit too ‘sciencey,’ it actually defines a straightforward concept. It is just a name for a sleeping pattern type where a person divides up their sleeping time into two main sessions.
For instance, you may catch most of your sleep during the night, then make up for the rest with a daytime siesta.
Characteristics of Biphasic Sleep:
- It is a sleep pattern where one sleeps in two different sessions within a 24-hour period.
- The two sessions could be at night or may consist of a longer session during the night and a shorter one during the day.
- It is different from monophasic sleep where one sleeps in one extended session, often at night.
- It is also different from polyphasic sleep where one sleeps more than twice within a 24-hour period.
Types of (Diphasic) Biphasic Sleep
Two Sessions at Night
This is where you sleep for a couple of hours, particularly around early nighttime or evening, waking up for a few of hours during the night before finally going to sleep for a couple more hours until early morning.
This sleeping style will yield approximately 6-8 hours of sleep.
One Session During the Day and One At Night
The amount of time you sleep at night and that you nap during the day is a matter of personal preference.
Some people are more active during the night meaning they can take longer hours sleeping during the day.
Some biphasic sleepers will sleep for like 6 or so hours at night and take a 20-minute nap in the afternoon while others prefer sleeping for shorter time periods (about 5-hours) at night and take longer naps (about 90 minutes) during the day.
This option, mainly referred to as siesta sleep, is one of the most common and is quite popular in most European cultures.
According to most biphasic sleepers, choosing the right approach will involve some trial and error. We are all different, so some people may find they are best suited with either one of the biphasic patterns mentioned above.
What is The Difference Between Polyphasic and Biphasic Sleep?
If you have tried researching biphasic sleep, chances are you have come across the term ‘polyphasic’ as well, right? So, how are they different?
Well, it isn’t that hard to explain really. Each word’s first syllable says it all.
The term “Bi” is of Latin origin and means “two” while “poly,” which is also Latin in nature, means “many.”
So, in essence, biphasic means two sessions within a 24-hour period and polyphasic means several sessions within the same period.
It is worth noting that polyphasic sleepers can adopt a variety of different sleeping shift patterns. For instance, polyphasic sleepers may:
- Sleep up to three times within a 24-hour period, a pattern known as triphasic sleep and involves sleeping for 90-minutes, staying awake for about 6 hours then sleeping for another 90-minutes and so forth for a total of 3-cycles.
- Sleep for longer periods of time at night (about 3-4 hours) and take several short naps during the day.
- Take two sleep shifts at night, and a siesta during the day.
It is worth noting that insomnia and other sleeping disorders aren’t the same as intentionally taking up a biphasic or polyphasic sleep pattern.
For some people, becoming a polyphasic sleeper is completely unintentional. Which means that they wake up a couple of times at night even if they do not want to.
At the end of the day, when trying to differentiate between polyphasic and biphasic sleep, the most important thing to remember is that polyphasic sleep involves more than two sleeping sessions while biphasic only involves two sessions.
Nevertheless, people will often notice a difference when they adopt and stick to one pattern consistently.
A Little Bit of History
While biphasic sleep may sound like a new idea to modern day sleepers who are accustomed to monophasic sleeping patterns, the truth is that it has been around for a long time now.
If you take into account the history of humankind, you will realize that the biphasic pattern was the norm for a major part of our history compared to sleeping through the night.
Data suggests that most people back in history would sleep for about 4-hours early in the night, wake up for about an hour, then go back to sleep for another 4-hours.
There are so many references that crop up throughout historical literature, diaries, medical texts and art with some historical figures like Chaucer and Homer referring to this concept in their work.
So, if that is the case then why is it that most people today only sleep once a day? Well, this can be attributed to the invention and introduction of the light bulb into our lives.
The light bulb is probably the number one reason why the western world has shifted away from the biphasic pattern of sleep.
The introduction of electricity meant that work hours could now be extended instead of them ending once daylight disappeared.
As a result, the amount of time for sleep at night was compressed, as most people now viewed enjoying two 4-hour sessions of sleep as a luxury.
Streetlights further encouraged nighttime socializing, which led to people staying out for longer, disrupting their ability to practice or enjoy the habit of sleeping twice a day or night.
As a result, most modern or urbanized people ended up eschewing their sleep pattern in favor of a monophasic sleeping habit.
However, according to some research conducted in the 1990s, people will naturally shift towards a biphasic sleep pattern when they are exposed to natural daylight and darkness patterns.
Nevertheless, you could still train yourself to adopt a biphasic pattern of sleep even in today’s fast-paced world.
Some Of The Benefits Biphasic Sleep Has to Offer
Ask yourself this question, why are some of today’s trendsetters and cultures valuing biphasic patterns of sleep? Well, it turns out that this sleeping style may offer several perks.
Here is a look at some of these benefits.
Biphasic Sleep may:
- Improve Cognitive function. Sleeping two times a day is thought to improve cognitive function partly because it enhances one’s capacity for concentration and focus and reduces feelings of tiredness. 
- Improve Productivity. Research indicates that a biphasic pattern of sleep may boost productivity especially considering the improved cognitive function mentioned above and increased alertness. These two factors alone will mean that you get more accomplished. What is more, an increase in productivity can never be accompanied by a sense of burnout or tiredness.
- Reduce Stress. Wakefulness-at-night sessions practiced during biphasic sleep patterns of yore were considered highly relaxing and were a vital way for people to cope with stress. There is a possibility that modern-day sleepers could benefit from the same.
- Yield The Benefits of Power Naps. According to recent studies, power naps can offer a range of benefits including an increased capacity to learn, memory recall and formation, creative problem solving, greater cognitive performance, and logical reasoning. At the same time, power naps could also reduce fatigue, reduce stress, decrease the chances of making errors while on the job, and increase mental alertness. 
- Enable Flexible Scheduling. Splitting up your daily sleep allotment into two separate sessions could offer you more flexibility, allowing you to juggle family, work and other responsibilities.
- Help with Insomnia. When people who have insomnia get to know that humans of long ago used to wake up at night, this could help overcome their anxiety regarding their conditions. When anxiety goes down, sleep will likely improve.
- Improve Dream Recall. Studies suggest that biphasic sleep could improve our ability to remember dreams, something that could give us even more access to the subconscious mind and may lead to us yielding personal insights about our thoughts and feelings.
The benefits of biphasic sleep are primarily attained by consistently practicing biphasic sleep. That’s because there is a transition period where your benefits may be reduced. 
The Potential Shortcomings of Biphasic Sleep
While the biphasic pattern of sleep poses several benefits, it still has some downsides.
First, it involves an adjustment period that may leave you feeling grumpy, groggy or even more tired. 
And don’t forget that you will have to shake up your entire sleep schedule, something that could disrupt your current social dynamics.
Furthermore, there is not enough research or evidence about the long-term effects of these sleeping patterns. Nevertheless, most studies suggest that biphasic patterns of sleep are relatively harmless.
As long as you are getting approximately 7-9 hours of sleep a night, then it is okay if you sleep in two sessions.
Who Is It Good for?
Everyone’s sleep preferences and needs are different and unique, which means biphasic sleep patterns are likely to be more suited for some more than others.
While scientists are not yet sure what factors will influence how a body responds to this sleeping pattern, one thing they know, is that some people require eight consecutive hours of sleep for them to function at their best and be well-rested.
Some, on the other hand, thrive on shorter sleep periods with one or two daytime naps.
There could be some genetic components at play here though.
For instance, there is a study that suggests that only 1-3% of the population performs well on just a couple hours of sleep a night. It could be because of a mutated gene.
However, for most of us, it is essential that we enjoy an extended period of good, quality sleep.
Luckily, biphasic patterns do not require that you only sleep for a few hours at night and is, therefore, much more accessible.
And then, there is the lifestyle element. For instance, people who juggle unusual family schedules may enjoy the flexibility a biphasic pattern has to offer.
At the end of the day though, sleeping patterns are not a one-size-fits-all kind of thing. The only way to determine the approach that best suits you is by experimenting with different sleep schedules until you find one that feels right for you.
Experimenting With Biphasic Sleep
If you are looking to give biphasic sleep a go, then here are some guidelines for you to consider to ensure that you set yourself up for a shot at success.
Choose A Sleep Pattern That Suits You
It is vital that you start by choosing a sleep pattern that suits you.
You could either settle for sleeping for approx. 6-hours at night and taking a twenty-minute nap during the day. Or you could go for sleeping 5-hours at night and taking a 60-90-minute nap during the day.
When looking for a style that works best for you, consider the times you normally feel sleepy and work with that.
Think About What You Are Trying To Achieve
What is your reason for trying a hand at biphasic sleeping? Is it because you want to improve productivity, reduce stress, boost cognitive functioning or is it for something entirely different?
Your answer to this question will influence how you approach the experiment. Identifying goals will help establish metrics that you can track as you try and make a difference in your life.
Consider keeping a sleep log to track progress and for adjusting your schedule as needed.
To Get All Of The Benefits Of Biphasic Sleep – Be Consistent
Sticking to a schedule is crucial when it comes to training your body to adjust to sleeping times. It helps ensure that you are getting restful sleep during sleep sessions.
Furthermore, an irregular sleep schedule could backfire, as inconsistency will lead to disrupted sleep, and that could lead to you performing poorly during your ‘awake’ hours.
Avoid Artificial Light
Artificial light has been known to disrupt our circadian rhythms, making it harder to fall and stay asleep during sleep sessions.
As such, it is advisable that you limit your exposure to artificial lights by turning off your TV and dimming the lights when it’s almost bedtime.
If you have opted to have a wakefulness period when you wake up in the night, then try and minimize artificial light exposure during that time since it may make it harder for you to fall back asleep.
Practice Proper Sleep Hygiene
Create an environment that is conducive for sleep. Doing so will increase your chances of falling and staying asleep during every sleep session.
Make sure that you sleep in a quiet, uncluttered, dark, and cool place and avoid exercising or drinking alcohol immediately before a sleep session.
Consult Your Physician
It is advisable that you consult your doctor before making any rash changes to your cycle, and seek advice on whether to take up a biphasic sleep pattern or not.
Your doctor should be able to tell you if there is anything related to your medical history that could affect your health should you change your sleep patterns.
This is particularly crucial if you suffer from chronic health conditions like depression and anxiety since messing up your sleep patterns could affect them.
Taking on the biphasic sleep pattern is not for everyone. However, for most people, switching from monophasic sleep to biphasic sleep presents them with some advantages ranging from greater productivity to flexible scheduling, to increased alertness during the day.
At the end of the day, it is up to you to decide if this is something you want to try out, but remember you are not obligated to do anything.
If it’s too much for you, then just stick to your normal sleeping pattern, just as long as you get six to nine hours of sleep.
The length of time that you sleep must provide for your sleeping through as many full sleep cycles as possible. See my article How Long Is A Sleep Cycle? A Closer Look At The Sleep Cycle
Also, you may be interested in: The Non-REM and REM Sleep Cycle Guide: Dreams & Health