Changes

==Mechanism==

==Mechanism==

The [[Polyphasic Discord|Polyphasic Discord Community]] has discovered some possible mechanics of Segmented sleep. The basis of Segmented sleep is the sleep peaks. During the early hours of the night (~21-24), when natural melatonin secretion starts, SWS can be gained efficiently. In EEG readings of adapted sleepers, the first core sleep is usually dense in SWS, whereas the second core sleep contains  primarily REM sleep. The divided core sleeps are thus denser in vital sleep stages, and allow for a small cut in total sleep with stable sleep times. Naps in the day are not needed because the amount of light sleep cut is small enough, and the day gap is also substantially shortened compared to a monophasic schedule.

The [[Polyphasic Discord|Polyphasic Discord Community]] has discovered some possible mechanics of Segmented sleep. The basis of Segmented sleep is the sleep peaks. During the early hours of the night (~21-24), when natural melatonin secretion starts, SWS can be gained efficiently. In EEG readings of adapted sleepers, the first core sleep is usually dense in SWS, whereas the second core sleep contains  primarily REM sleep. The divided core sleeps are thus denser in vital sleep stages, and allow for a small cut in total sleep with stable sleep times. Naps in the day are often not required due to segmented's longer cores perserving light sleep in addition to the the nightly core gap reducing the amount of time awake between the cores during the day.

Both core sleeps are scheduled to be 3.5 hours by default because the sleep cycles are known to lengthen to about 105 minutes from the approximately 90-minute cycles on monophasic sleep. This would also explain the viability of the schedule despite having fewer cycles.

Both core sleeps are scheduled to be 3.5 hours by default because the sleep cycles are known to lengthen to about 105 minutes from the approximately 90-minute cycles on monophasic sleep. This would also explain the viability of the schedule despite having fewer cycles.

The wake gap between each core (known as "core gap") should at least 90 minutes, with a longer gap recommended (~2.5-3 hours) for non-natural Segmented sleepers. The reason for this is to prevent the cores from becoming interrupted sleep, in which there is a only a brief period of awakening during sleep, before the sleeper goes back to sleep, which disrupts the sleep cycle and drastically reduces sleep quality.  

The wake gap between each core (known as "core gap") should at least 90 minutes, with a longer gap recommended (~2.5-3 hours) for non-natural Segmented sleepers. The reason for this is to prevent the cores from becoming interrupted sleep. Interupted sleep is when there is a only a brief period of awakening before going back to sleep which disrupts the sleep cycle and drastically reduces sleep quality.  

Staying awake for at least ~90m will usually prevent this, so that the second core starts in a new sleep cycle. A core gap that is too short is unlikely to be productive time, and it may also be difficult to fall asleep as not enough sleep pressure has been accumulated. The original default recommendation was a 2-hour gap, but has since been changed to 3 hours as some people were unable to fully adapt to the 2-hour gap version.

Staying awake for at least ~90m will usually prevent this, so that the second core starts in a new sleep cycle. A core gap that is too short is unlikely to be productive time, and may also result in the sleeper having a difficult time falling asleep due to insufficient sleep pressure. The original default recommendation was a 2-hour gap, but has since been changed to 3 hours as some were unable to fully adapt to the 2-hour gap version.

== Adaptation==

== Adaptation==

For naturally Segmented sleepers, the adaptation is easy. For non-natural Segmented sleepers, adapting to Segmented may be harder than adapting to [[Siesta]] or [[E1]]. Waking up from the first core could be difficult. Boredom during the night gap can make it hard to stay awake. The second core sleep containing much REM sleep can also grogginess or dizziness upon waking. Over time, with strict adherence to the schedule, these issues should disappear.  

For naturally Segmented sleepers, adaptation is easy. For non-natural Segmented sleepers, adapting to Segmented may be harder than adapting to [[Siesta]] or [[E1]]. Waking up from the first core could be difficult. Boredom during the night gap can make it hard to stay awake. The second core sleep containing much REM sleep can also result in grogginess or dizziness upon waking. Over time, with strict adherence to the schedule, these issues should disappear.  

After Segmented, there is a gradual adaptation route to [[Dual core]] schedules, and also [[Triphasic]], as the division of core sleeps had been learned.

After Segmented, there is a gradual adaptation route to [[Dual core]] schedules, and also [[Triphasic]], as the division of core sleeps had been learned.

==Variants==

==Variants==

While the default dual 3.5 hour core variant has had the most success, a few other combinations are also plausible and have been adapted to in the past. Beginners can attempt these variants, with some precautions.

While the default dual 3.5 hour core variant has had the most success, a few other combinations are also feasible and have been adapted to in the past. Beginners can attempt these variants, with some precautions.

=== 6-hour total sleep ===

=== 6-hour total sleep ===

These are 2 modified variants that have reported some success over the years. Since the total sleep is only 6 hours, it may be suitable for those with slightly below average monophasic baselines (~7h). One problem with this schedule would be a circadian dip in the early afternoon hours, without naps to address them. Because more light sleep has been cut compared to the default variant, staying awake could be more difficult.

These are 2 modified variants that have reported some success over the years. Since the total sleep is only 6 hours, it may be suitable for those with slightly below average monophasic baselines (~7h). One problem with this schedule would be a circadian dip in the early afternoon hours, without naps to address them. Because more light sleep has been cut compared to the default variant, staying awake could be more difficult.

The wake gap between each core should be at least 4 hours to cover the SWS and REM peaks more efficiently, as well as to reduce the length of the day gap. The overall adaptation may be more difficult than the standard version because of the reduced sleep time. The benefit is the added extra time at night, and only needing to sleep at night without using daytime naps.

The wake gap between each core should be at least 4 hours to cover the SWS and REM peaks more efficiently, as well as to reduce the length of the day gap. The overall adaptation may be more difficult than the standard version because of reduced sleep time. The benefit is the added extra time at night, and only needing to sleep at night without daytime naps.

The difference between 4.5-1.5 and 3-3 core distribution is that those with more SWS requirements can attempt the former option, while those needing similar amounts of REM and SWS can pick the latter. Overall, the 3-3 variant better balances sleep stages, and has seen more success overall than the 4.5-1.5 variant.

The difference between 4.5-1.5 and 3-3 core distribution is that those with more SWS requirements can attempt the former option, while those needing similar amounts of REM and SWS can pick the latter. Overall, the 3-3 variant better balances sleep stages, and has seen more success overall than the 4.5-1.5 variant.

The main issue with this is that it is impossible for an average sleeper (90m SWS need) to gain all the needed SWS in the first core, the second core will have to provide the remaining SWS, and pushing the second core to late hours of the night may increase the difficulty of the process.  

The main issue with this is that it is impossible for an average sleeper (90m SWS need) to gain all the needed SWS in the first core, the second core will have to provide the remaining SWS, and pushing the second core to late hours of the night may increase the difficulty of the process.  

Similar to the default schedule, this variant also takes away some of the social time in the evening; social time is traded for the time in core gap.

Similar to the default schedule, this variant also takes away some of the social time in the evening in exchange for time in the core gap.

[[File:Siesta-hybrid.png|right|thumb|Segmented-Siesta hybrid]]

[[File:Siesta-hybrid.png|right|thumb|Segmented-Siesta hybrid]]

Alternatively, Segmented may be scheduled with one core at night and another core in the day. Only a few successes have been reported thus far. This variant looks like Siesta with a long daytime core, and both core sleeps miss the peaks. The dark period should be 2-3h before the night core, and continue for ~2h after it to stabilize the circadian rhythm.  

Alternatively, Segmented may be scheduled with one core at night and another core in the day. Only a few successes have been reported thus far. This variant looks like Siesta with a long daytime core, and both core sleeps miss the peaks. The dark period should be 2-3h before the night core, and continue for ~2h after it to stabilize the circadian rhythm.  

Adaptations to this would be much more difficult than a regular Segmented schedule, because skipping both sleep peaks can greatly hinder quality sleep. Over the course of adaptation, staying awake during the graveyard and morning hours will be tough, and having a long sleep in the day may disrupt the circadian rhythm.  

Adaptations to this would be much more difficult than a regular Segmented schedule, because skipping both sleep peaks can greatly hinder sleep quality. Over the course of adaptation, staying awake during the graveyard and morning hours will be tough, and having a long sleep in the day may disrupt the circadian rhythm.  

===Night shift===

===Night shift===

[[File:Shift Work.png|right|thumb|A Variant for Third Shift]]

[[File:Shift Work.png|right|thumb|A Variant for Third Shift]]

The idea is to have a core sleep after the work period, and then a core sleep before work. Little is known about this scheduling variant, and adaptations have been overall not unsuccessful. Due to the circadian rhythm disruption it causes, night shift has always been associated with health concerns, and sleeping this way will likely be no different.  

The idea is to have a core sleep after the work period, and then a core sleep before work. Little is known about this scheduling variant, and adaptations have been overall not unsuccessful. Due to the circadian rhythm disruption it causes.  

There have been at least a couple failures while deploying Segmented sleep for shift work. This is expected, as overall rates of success is very low for night shift workers.  

There have been at least a couple failures while attempting Segmented sleep for shift work. This is expected, as overall rates of success is very low for night shift workers.  

==Lifestyle Considerations==

==Lifestyle Considerations==

Segmented, which allows for a range of schedule options, can be suitable for many. It greatly benefits those who naturally wake up during the night, and also allows those who are unable to take a daytime nap to still polyphasically.

Segmented, which allows for a range of schedule options, can be suitable for many. It greatly benefits those who naturally wake up during the night, and also allows those who are unable to take a daytime nap to still sleep polyphasically.

Before one transitions to Segmented, it is important to plan ahead what to do during the core gap, as staying awake at night when everyone else is sleeping and having nothing to do can become difficult. For naturally segmented sleepers, this is less of a problem. Here are a few tips:

Before one transitions to Segmented, it is important to plan what to do during the core gap. Staying awake with few things to do  while everyone else is sleeping can be difficult. For naturally segmented sleepers, this is less of a problem. Here are a few tips:

* Make a list of what activities or tasks that can be much better done at night. This includes entertainment. Being alone can also be an advantage at times. Be sure to consider that these hours must be in [[dark period]], in which you will be wearing [[Dark_period#Goggles|goggles]], and as such will not be able to see colors.

* Make a list of what activities or tasks that are well suited to being done during the night. This includes entertainment! Being alone can also be an advantage at times. Be sure to consider that these hours must be in [[dark period]], in which you will be wearing [[Dark_period#Goggles|goggles]], and as such will not be able to differentiate colors.

* Dedicate time for self-care. The core gap can be useful for relaxation after long days at work. Self-care can include autogenic training, [[meditation]], [[yoga]], and stretching. Note that it may be unadvisable to do these things when you are having problems staying awake.

* Dedicate time for self-care. The core gap can be useful for relaxation after long days at work. Self-care can include autogenic training, [[meditation]], [[yoga]], and stretching. Note that it may be unadvisable to do these things when you are having problems staying awake.

* Plan for your day. People often have a lot to work on and care about. No matter how much extra awake time you might have, time management is always important.

* Plan for your day. People often have a lot to work on and care about. No matter how much extra awake time you might have, time management is always important.

* Segmented is the only schedule that easily allows >12h of continuous wake time without needing any naps. This can allow many people who are unable to take naps to sleep polyphasically.  

* Segmented is the only schedule that easily allows >12h of continuous wake time without needing any naps. This can allow many people who are unable to take naps to sleep polyphasically.  

* Segmented offers a relatively high amount of sleep, it is viable to schedule the first croe later than normal to start at ~23 to allow some more evening events. The only thing to note, is that the late first core likely will delay the end of the second core, and may interfere with your morning activities. Under normal scheduling, however, there will be more limited evening social time on Segmented sleep.  

* Segmented offers a relatively high amount tst (total sleep time). It is viable to schedule the first core later than normal, ~23, to allow evening events. The only thing to note, though, is that a late first core likely will delay the end of the second core, and may interfere with your morning activities. Under normal scheduling, however, there will be more limited evening social time on Segmented sleep.

* Segmented can become somewhat flexible after adaptation. Some experienced sleepers have reported being able to flex at least one of the core sleeps. Being able to flex the core sleeps allows for more freedom in controlling the length of core gap to suit one's schedule. For example, on days with little to do, the core gap can shrink down a bit, so that the second core can start earlier than usual, or vice versa. When sudden events occur that would require skipping sleep, Segmented also allows relatively fast recovery afterwards.  

* Segmented can become somewhat flexible after adaptation. Some experienced sleepers have reported being able to flex at least one of the core sleeps. Being able to flex the core sleeps allows for more freedom in controlling the length of core gap to suit one's schedule. For example, on days with little to do, the core gap can shrink down a bit, so that the second core can start earlier than usual, or vice versa. When sudden events occur that would require skipping sleep, Segmented also allows relatively fast recovery afterwards.  

* Segmented sleep, especially the extended variant with a longer first core, can support intense physical exercise.

* Segmented sleep, especially the extended variant with a longer first core, can support intense physical exercise.

* Vivid dreaming experiences have been reported on the schedule over the years, most of which come from this second core.

* Vivid dreaming experiences have been reported on the schedule over the years, most of which come from the second core.

== References ==

== References ==

<references />{{TNT|Polyphasic Sleep Schedules}}

<references />{{TNT|Polyphasic Sleep Schedules}}

[[Category:Schedules]]

[[Category:Schedules]]