Lifestyle Considerations

Introduction

There are a lot of lifestyle considerations to bear in mind. In addition, choosing a correct and maintainable schedule is important. However, it is also very specific to personal life circumstances. There are several factors to consider, such as exams coming up, work schedules, one’s age or the ability to sleep during the day. Thus, you should carefully read through this whole article and consider every aspect of your lifestyle first. Then, determine which schedules are sustainable and whether you have the time and the necessary flexibility to adapt and maintain the given schedule.

Even though this article covers many common lifestyle considerations, it does not account for every possible situation. Thus, if you have questions about special circumstances not present in this article, consider joining the Discord chat server or Reddit. You will be likely to come across someone with more experience or have circumstances similar to yours.

Age

People who are younger generally require more sleep. This particularly affects those who are underage (under 18 years old) and have not fully matured yet. This is because they are still growing both mentally and physically1.

  • Extra SWS time is necessary to support bodily growth, learning, and memory retention.
  • The total amount of light sleep is lower and there is a higher percentage of REM and SWS in daily sleep totals2.
  • Because light sleep could play a part in development3,4,getting as much sleep as possible is also likely necessary. Consequently, the total amount of viable daily sleep reduction is very small.
  • Underage people should also absolutely avoid any polyphasic sleep schedules with significant sleep reduction. 

General guidelines

The polyphasic sleep community uses the following lifestyle consideration values as a baseline:

  • <16 years: Sleeping the recommended amounts is highly encouraged. Both the brain and the body are in full development and highly sensitive. The negative side effects of polyphasic sleep are by large unknown; thus, there is a good reason to take precautions similar to nicotine or alcohol. Both of these are equally unadvised during development. With artificial lighting causing the advancement of circadian rhythm and an early start of the school day, segmenting their sleep may be helpful in achieving refreshing sleep duration that would otherwise not be possible.
  • 16 to 18 years: At least 6h of sleep, and potentially more if possible. The body and brain are both still developing, but at a lesser extent than previously. However, this period is one of the most important ones during life. In modern society, high school performance has great impact on future outlooks. It may be worth taking this into account as improper experimentation with your sleep can affect the day-to-day performance.
  • 18 to 21 years: At least 5h of sleep. The body has developed to some extent; however, the brain is still developing. In addition, this development process may also conclude later in some other individuals. 
  • 21 to 25 years: Over 4h; the brain can still be in the final stages of development. Dropping below 4h is generally advised against, even after 25. Furthermore, younger adults have generally less structured lifestyles. You should really consider this factor if it applies to you. More details are in later sections. 

More data on adolescent sleep

In addition to the general guidelines above, it is important to consider that some people, especially males, can have growth spurts as late as at 19 years5. During this period, SWS need increases. It is debatable whether people who are 17 can actually drop down to 5h of sleep, but it is probably best to stay above that benchmark. The rational part of the brain develops until the age of about 25 years old6 (possibly longer7,8). This means the safest course of action is to avoid reducing the total amount of sleep at least until that age. This also means no experimenting with extreme schedules like Uberman and Dymaxion until later.

A growing body of scientific research support these recommendations:

  • Adolescents require > 9 h of sleep at night.  Some even require additional daytime sleep.
  • In controlled conditions with 10 hours allocated for sleep, 10-17-year-olds needed 9.25 h of sleep per night regardless of age. In addition, at mid-puberty, there was an increased tendency for daytime sleep even with sufficient night-time sleep9.
  • Delayed sleep-wake behavior present in greatest extent in Asian cultures. As a result, this causes decrease in total sleep during adolescence (for review, see10). This is regardless of the amount of sleep needed to achieve optimal day-to-day performance.
  • Many studies have demonstrated that on average they obtain between 7.5 and 8.5 h per night; about a quarter of adolescents obtaining < 6.5 h per night and only 15% obtaining 8.5 h or more9,11.

Exercise

Exercising is also a vital lifestyle consideration that many people seek together with polyphasic sleeping. In general, activities which involve only light-to-moderate exercise (e.g. light cardio or light sports) should not have any significant impact on sleep architecture except in extreme polyphasic schedules. However, very physically strenuous activities or high-intensity exercises (e.g. heavy sports, weight lifting, HIIT, etc.) should be considered more carefully.

  • Additional sleep time is a requirement because muscles and tissues need repairing. This process reflects an increased daily SWS requirement12.
  • The increase in SWS usually causes a reduction in the total time spent in NREM212.
  • The total amount of possible daily sleep reduction for highly physically active people reduces, because they require more sleep overall.

Moreover, people engaging in high levels of exercising reportedly are able to take on a polyphasic schedule with 3 uninterrupted core cycles without any problems.

Tips during adaptation

  • However, additional naps compared to the standard schedules will be critical to allow for more SWS over REM in the core.
  • During adaptation, it is best to not raise the SWS need unnecessarily. This could lead to an elevated risk of entering an SWS rebound. Typically, you can continue the familiar level of physical exertion after you have fully adapted to your new sleep schedule.
  • While significant muscle and tissue repairing generally increases sleep duration13, exercise and an active lifestyle can reduce feeling of constant tiredness. Some inactive people experience tiredness on regular sleep schedules longer than general recommendation.
  • Many people also find physical activity helpful during adaptation; some forms of exercising can help combat the urge to sleep. Especially during the second and third adaptation stage, oversleeps are mostly present with inactivity. 

Tips after adaptation

  • After adaptation, sporadically increasing the length of the core by one full cycle to support more exercise is possible. However, this should not be too often. Some decompression or adaptation setback can occur, which can take a few days to bounce back.
  • Doing this once a week at most will greatly stabilize your sleep schedule and prevent significant fluctuations in energy or oversleeping chances. 
  • Exercising too close to a sleep block can also heavily affect sleep quality; thus, it is best to leave a gap of at least 2h between exercise and before sleep14. If you know a shorter gap doesn’t hinder your sleep, you can ignore this rule. 

Due to a significant SWS deprivation during adaptation on schedules with extreme levels of sleep reduction, especially nap-only schedules with severe SWS rebounds during adaptation, you should avoid overexertion. It may take extra time to recover even after light or moderate levels of exercise, especially with a physically active job. After the adaptation period, this effect should be less noticeable but will likely persist on extreme schedules.

Important Note

  • Exercising can contribute mildly to establishing the circadian rhythm by setting the new circadian morning15.
  • There should be no heavy exercising during the dark period, although the circadian effect is minor compared to light exposure.
  • Night shift workers may opt to use exercise as a way to favorably shift their circadian rhythm. This would serve to better accommodate for their sleep and work schedule.

Growth hormone

Human growth hormone (HGH) is a hormone that affects skeletal muscle growth1617 and skeletal growth1819. It is, therefore, very important that adolescents and children produce a sufficient amount.

  • SWS in the first sleep cycle typically secretes HGH20. This isn’t an issue for polyphasic sleepers who follow the sleep recommendations of this guide. They should always have a core dedicated to SWS; therefore, they will achieve the necessary, uninterrupted SWS for adequate HGH release.
  • On another spectrum, this evidence strengthens the idea that adolescents should never attempt nap-only schedules. Such a sleeping schedule can severely butcher their own GH. 

Dark period

Determine whether the filtering glasses are doing their job sufficiently by using our light filtering calculator!

Melatonin mechanisms

Melatonin is important for proper SWS initiation and healthy sleep architecture21.

  • An inherent feature of circadian rhythm and melatonin secretion is the suppression and delay of onset following exposure to blue and green light (wavelengths 400-530 nm), by 65-81%22, or roughly 2h23.
  • This feature of the rhythmic processes has been very effective in aiding the entrainment of circadian rhythms with the day-night cycle as blue light was only available during day. However, in recent years, it became increasingly apparent that this can have adverse side effects of circadian misalignment. This effect worsens when combined with exposure to artificial lighting during night time.
  • Some studies suggest that as little as 100 lux of room lights for 6.5 hours24, or 250 lux (office lighting) is enough to completely disrupt the melatonin levels25. These findings warrant minimizing all non-red light types during the dark period. This should not, however, be done in exchange for increasing brightness of red light sources. Red light may have the same effect as light in the blue/green frequencies, but to a lesser extent.
  • Some studies have linked the misalignment of circadian processes with elevated risks of developing cardiovascular diseases26, diabetes27 and cancer28;hence, it is unlikely the impact on sleep is the only possible negative outcome.

Dark period setup

  • The dark period should start 2-3h prior to the core. This could be the first core on DC schedules or night core on TC schedules for example.
  • The dark period should continue for 6-12h (preferably 8-10h) after it begins. This period also includes sleeping hours. The reason it should continue even after your wake time, if you have a short core, is to ensure the stability of the circadian rhythm.
  • Light29 and food30 can alter the start of the circadian day.  This in return results in a shift of the SWS and REM peaks accordingly. Darkness is still preferable over red light.
  • One can simply block lights by wearing blue-green light blocking glasses like red colored laser safety goggles. Make sure the glasses block the right wavelengths; many glasses (like yellow-tinted ones) actually allow green light to leak through. Having side protection is also desirable.
  • Using programs such as F.lux and Sunsetscreen on a low Kelvin setting (around 1000K) is also possible if you’re only exposing yourself to light from screens.
  • Using red light bulbs is also an option.

Schedule line specifics

  • Dual core: If your cores are within 5h from each other, then the dark period should cover the whole core gap.
  • Everyman: If the first nap is relatively close to the core, you should extend the dark period until the nap. Try to have the dark period between 8 and 12 hours long.
  • Tri core:
  1. For Triphasic, the dark period should cover the wake gap between two cores at night.
  2. For TC1 and TC2, the dark period should cover at least two of the cores. This is according to their sleep placements relative to the local time.
  • For other schedules, a good rule is to follow the day-night cycle of your country. However, if you live in location near the poles, you may want to create an artificial light and dark period to establish a stable cycle over the course of the year. This also protects you from any seasonal affective disorders due to the greatly fluctuating light levels.

Meal time

  • Fasting (consuming only water) should coincide with the dark period. Nighttime eating has a strong correlation with an increased risk of some diseases. This include night eating syndrome and sleep-related eating disorder. Furthermore, both of these diseases often result in an increase of body mass, obesity, psychiatric disturbances31, diabetes32, delayed sleep onset, worse quality sleep33 and improperly set the circadian morning.
  • Aim to have the fast last for at least 8-12 hours34. If it is too hard to curb the hunger, try to minimize the consumption of carbohydrates in the evening. In addition, only consume low caloric foods with low glycemic index (GI) instead. This has anecdotally helped people, mostly because of the slow blood sugar and energy release.

A shift in Circadian Rhythm

Check out this blog post for a more in-depth look into how to shift circadian rhythms and determine the natural sleep peaks!

A circadian rhythm shifted in relation to the natural day-night cycle may be desirable to better accommodate for a particular sleep schedule in terms of alignment of sleep blocks with the sleep stage peaks. This is generally not advisable when working a day job or participating in daytime activities; Thus, it requires extra care and planning. Nevertheless, many people have to do this to be able to handle a third shift or participate in  late evening social events. etc. There is only one main method to shifting the circadian rhythm; additionally, it is going to take some time.

Circadian cues

  • Stop the dark period at the desired new circadian morning, and use light and food to start it.
  • This method is also useful for people who are adapted to a polyphasic sleeping schedule and want to rotate their schedule. Confusing the circadian rhythm is not something you want to do while on a fixed circadian rhythm. This is the best and preferred way to adapt to a new circadian time.
  • Academic researchers called Entrain35 created an app to reduce jet lag. The app designs optimal schedules for shifting the circadian rhythm. It may work with the slow circadian shift, as its design is to adjust the circadian rhythm optimally. It is, however, advised that polyphasic sleepers do not submit any of their results through the app. This is because these researchers are interested in results related to jet lag and they can use the results for different purposes. This would eventually skew the results. 
  • Using light and food to wake up and having a set dark period should be satisfactory. However, if the circadian rhythm shifts a lot compared to the local day/night cycle, the temperature cycle is going to be useful. Exercising during the circadian morning could also be beneficial.

If the circadian is unintentionally shifted, for example a dark period that is too short, it can lead to a reduced amount of SWS or REM in the core. This is because the sleep peaks have moved. This can create a series of problems; these include, but not limited to, feelings of tiredness, sleep deprivation, potential SWS rebounds. Overall, these issues would only drastically increase the chance of oversleeping.

Polyphasic adaptation preparation

Most notably, an increased amount of sleep deprivation will cause difficulties when attempting to shift the circadian rhythm. Experiments with phase shifts of the circadian rhythm with increased sleep homeostatic pressure suggest that the circadian clock is less susceptible to phase shifts when sleep pressure is high36. What this means is:

  • If you aim to shift your circadian rhythm, you should preferably not combine it with a polyphasic sleep adaptation.
  • The better approach would be to first spend time shifting the rhythm.
  • Then, start the polyphasic adaptation after completing your own circadian shift.

Menstruation

During a polyphasic adaptation, one’s period might be affected because of the hormonal imbalance. It might happen earlier, later or be skipped completely.

  • The SWS need can increase to some extent by periods. This means it is best to try to start adaptation right after the period.
  • Alternatively, time it so that the period occurs during stage 1.
  • Extending one’s core by a full cycle during this time might be necessary after adaptation (at least some days of the menstruation cycle). However, it is unclear and probably highly individual; schedules that have over 2 cycles in the SWS core may or may not require the extension.

Religion

When designing a polyphasic sleeping schedule, one should take possible prayer times and fasts into consideration.

  • Since the prayer times could move on a daily basis, you should aim to have a clear one or preferably two-month timespan. This is to make sure no prayer times will interfere with sleep times during adaptation.
  • When the time comes, it may be necessary to reschedule around these times. Methods include doing a DST shift, flexing sleep or simply shifting nap times if you’ve been adapted for a while.
  • Switching to a less extreme schedule could be wise during fasts like Ramadan; however, this depends on what country you live in and when it occurs. Note that eating will likely set a new circadian morning if done during the night. It will cause SWS and REM peaks to move.
  • Adapting during Ramadan could pose problems as well. Eating is one way to combat sleep deprivation; in addition, energy expenditure would increase food consumption requirement during the prolonged wake time. The lowered amounts of energy will also likely increase the risk of oversleeping or giving up.

Room temperature when sleeping

It is possible that room temperature has a notable impact on sleep quality. Some people have reported having difficulty sleeping in a room that is too cold or too hot.

Further research is mandatory in this area to determine the full extent of impact and the most optimal temperature range for a polyphasic sleep setting. As an example, monophasic sleepers seem to thrive in temperatures between 15 and 20 degrees Celsius37.

However, at least one study demonstrates improved sleep quality in a slightly cool environment38. Furthermore, another study suggests that keeping hands and feet slightly warmer can boost sleep quality39. This includes wearing gloves and socks.

Meditation versus sleep

Some people have claimed that meditation can replace sleep. While it is true that meditation can aid with restfulness, there is a severe lack of evidence for its ability to replace sleep. There is also a risk of falling asleep during meditation. Further research will be valuable in this area to determine the effect of meditation restfulness.

Masturbation, porn and sex

Check out this blog post for an in-depth look into how the no-fap lifestyle can benefit polyphasic sleepers!

Masturbation, porn and sex likely make you subsequently feel tired and want to sleep. Thus, if you want to engage in these activities, it may be better to do them shortly before sleeping. Some people in the polyphasic sleeping community do not masturbate at all; whether this is helpful or not remains in dispute. All in all, with all current evidences, it is purely a matter of preference.

Long-term metabolic effects

It appears that even after successful adaptation, there are likely long-term metabolic effects of polyphasic sleeping. These effects seem even more apparent on extreme schedules. There is plenty of evidence to support this; additionally, the consensus from veterans on extreme schedules seems to be the enhanced hunger.

  • A case of this is Aeia, who reportedly lived on Uberman between June 2009 and March 2010. She also logged her experience on her YouTube channel. She eventually quit because she was gaining  weight regardless of diets. This coincides with research linking increased risk of obesity to night-time eating on regular sleep schedules; as a result, it may suggest that polyphasic sleep is no different in this aspect40.
  • Whether keeping an intermittent fast during the night period would completely mitigate this issue is unclear; however, the association of obesity with night time eating insinuates that reducing nighttime eating could significantly help people who suffer.
  • The energy from food intake can often counter sleepiness that may otherwise occur from having low volumes of sleep. This process may require a diet based on energy sources with slower release (protein and low GI food). There may also have to be an increased in food intake during the adaptation period. This is because it is generally more demanding than maintaining the schedule afterwards.

Daylight saving time

In most parts of the world, the clocks move forward in the spring and then backwards again in the autumn. This can interfere with polyphasic scheduling.

  • In general, you should try to stick to all of your sleep times during the DST changeover.
  • Sleep blocks should have same duration throughout
  • Sleep blocks near to or overlap the border may need some tweaks in their timing to alleviate excess sleep deprivation. Most polyphasers do not find this a considerable issue.

If the DST changeover is just after you start your schedule, you might want to start sleeping on the new time zone early to make sure the adaptation period keeps consistent scheduling. Otherwise, stay on the former scheduled time until adaptation begins.

If you plan on doing the DST change, make a full switch to the new sleep time cold turkey. Some people have reported grogginess and malaise from a gradual, slow transition with a couple minutes from day to day.

Travelling

Travelling while maintaining a polyphasic schedule is possible, but overall hard to pull off. If there are changes in time zones during adaptation, there are three recommend options:

  • Sticking with the original schedule
  • Rotating the schedule to fit the new time zone
  • Returning to monophasic sleep

The optimal route is to stick with the original schedule during the travel. Most notably, the dark period and a daylight lamp should make this manageable. However, depending on the duration and nature of the stay, rotating the schedule may or may not be possible.

  • Note that rotating the schedule will set adaptation progress back. The setback of around a week for each rotation is a good estimate, but it is dependent on several factors.
  • During adaptation, it is important to stick to all sleeping times. As a result, many people prefer starting their adaptation after they have reached a new time zone.
  • After being adapted for at least a month flexing is likely the best logical choice if nap times are missed (See Flexing). Starting a gradual adaptation or temporarily switching over to a harder schedule are also viable options. 

Tips for jet lag

Jet lag happens when you travel through different time zones. If you change your schedule during the stay, you will initially struggle to fall asleep fast in the new time zone. Thus, your schedule will suffer. Depending on how long your trip is, how long you stay in the new region, and how long you have been polyphasic, the travel can be hard or relatively easy. This will reflect on the need to re-adapt to the schedule during and after the trip. Another factor to consider is the possibility to maintain the schedule on the plane and in the airport.

  • If you have decided to return to monophasic sleep, just rest when you feel sleepy enough.
  • Try to get a core sleep or a nap in the plane. Time it so that when the plane lands, you wake up.

Tips to maintain a schedule

Try minimizing the over- and undersleeps if you can only stick to your schedule. 

  • Use alarms wisely in the plane. Mechanical alarm clocks as backups are smart, as there could be problems with phones.
  • Nap in the airport if necessary. However, try not to take a core in the airports, as you will be vulnerable to thefts.
  • Align your core time with the flight so that you can sleep most of it during the flight.
  • Prepare a “do not disturb” sign, with a sleeping mask and airplane pillow if possible.
  • Tactical oversleeps could possibly be an idea during this critical time. Your safety and well-being should be a higher priority than adapting quickly. Thus, if you have to skip several naps or parts of the core, taking more naps could benefit you.

Main author: Crimson

Page last updated: 24 December 2020

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