Changes

As with other Everyman schedules, the [[Cores|core]] sleep should provide most or all of the needed amount of [[wikipedia:Slow-wave_sleep|SWS]], whereas the naps provide [[wikipedia:Rapid_eye_movement_sleep|REM]] sleep and traces of [[wikipedia:Non-rapid_eye_movement_sleep|light sleep]]. However, unlike on [[E3]], the core sleep is simply not long enough to cover an average 90-120 minute SWS requirement. For this reason, at least one nap is likely to contain SWS, especially the last one near the evening.  

As with other Everyman schedules, the [[Cores|core]] sleep should provide most or all of the needed amount of [[wikipedia:Slow-wave_sleep|SWS]], whereas the naps provide [[wikipedia:Rapid_eye_movement_sleep|REM]] sleep and traces of [[wikipedia:Non-rapid_eye_movement_sleep|light sleep]]. However, unlike on [[E3]], the core sleep is simply not long enough to cover an average 90-120 minute SWS requirement. For this reason, at least one nap is likely to contain SWS, especially the last one near the evening.  

Similar to E3, the core should be placed relatively early in the SWS peak. In terms of sleep placements, E4 resembles [[DC3]], but with the second core being replaced with a nap. The gaps follow circadian sleep pressures, which are higher in the night and the morning, and lower in the afternoon. The 4-hour wake gaps between naps may fit into the '''[[wikipedia:Basic_rest–activity_cycle|BRACs]]'''. Since it is usually easier to stay awake in the afternoon and evening hours, the last wake gap before core is somewhat longer.   

Similar to E3, the core should be placed relatively early in the SWS peak. In terms of sleep placements, E4 resembles [[DC3]], but with the second core being replaced with a nap. The gaps follow circadian sleep pressures, which are higher in the night and the morning, and lower in the afternoon. The 4-hour wake gaps between naps may fit into the [[wikipedia:Basic_rest–activity_cycle|BRACs]]. Since it is usually easier to stay awake in the afternoon and evening hours, the last wake gap before core is somewhat longer.   

The sleep cycle in the core may naturally compress to as little as 60 minutes, which is caused by the greatly reduced total sleep and a high frequency of sleeps. That means its core duration is actually more than one full cycle, risking mid-cycle wakes until the brain adapts by placing light sleep at the trained wake time.  

The sleep cycle in the core may naturally compress to as little as 60 minutes, which is caused by the greatly reduced total sleep and a high frequency of sleeps. That means its core duration is actually more than one full cycle, risking mid-cycle wakes until the brain adapts by placing light sleep at the trained wake time.  

==Adaptation==

==Adaptation==

Adaptation to E4 is severely more difficult than to E3, because the removal of 1 core cycle makes it impossible for all SWS baseline to be protected. Even if it is (because of lower requirements), REM sleep becomes troubled because there is limited space in the core that would provide REM sleep, and the naps do not guarantee REM, or not consistently (especially naps after ~3-4 PM). Because it is not possible for an average vital sleep baseline (~90m REM and ~90m SWS) to be sustained on this schedule, these individuals will incur chronic [[wikipedia:Sleep_deprivation|sleep deprivation]] on this schedule.  

{{further|Uberman#Adaptation}}

Adapting to E4 is very harsh, if at all possible, involving extreme levels of sleep deprivation, similar to a milder version of Uberman. SWS is almost certainly cut short at the start of the adaptation, and it is very difficult to fit all of the needed amount into the short core. REM sleep will need to almost entirely be moved to naps. Sleepers with average vital sleep baselines (~90 minutes each of SWS and REM sleep) are unlikely to be able to sustain this schedule, and will likely incur chronic [[wikipedia:Sleep_deprivation|sleep deprivation]] should they remain on the schedule.  

Though it is possible to transition to E4 as a '''[[gradual adaptation]]''' from E3, so far this has reported no success rate. It is likely that adaptation to E3 is already overbearing at that point, and another immediate transition to E4, which is below the minimum sleep threshold, is the limitation that most people cannot get over. '''[[Cold turkey|Cold turkey method]]''', however, accounts for all the successful adaptations (including the '''extended''' version). E4 is also an option to fall back on if Uberman fails, but so far no one has been able to pull this off, either.  

It may be possible to transition to E4 as a [[gradual adaptation]] from E3, but no one has successfully adapted this way. As E4 is likely below the threshold for many people, this transition may be impossible regardless of the method. The few people who have adapted to it so far did so [[cold turkey]]. E4 can also be a fallback for Uberman fails, but it has also not been sustainable for most people who attempted.  

When adaptation first begins, as usual sleepers are expected to not fall asleep in some naps, or all of the naps. However, as sleep debt quickly accumulates, it will be easy to do so, and [[4-Stages Adaptation Model#Stage3|Stage 3]] is expected to arrive in a matter of days. Since no vital sleep baseline is protected, [[wikipedia:Sleep_deprivation|sleep deprivation]] will continually build up rather than getting relieved by the humble amount of total sleep on the schedule. An extreme adaptation is then required to reach the equilibrium of SWS and REM in all sleep blocks to be able to adapt. As with Uberman, any oversleeps greater than a rare 10m or so will be devastating to the adaptation process that requires both strict circadian entrainment and severe homeostatic pressure.

When adaptation first begins, as usual, sleepers are expected to fall asleep in only some naps. However, as sleep debt quickly accumulates, it will be easier to fall asleep. [[4-Stages Adaptation Model#Stage3|Stage 3]] is expected to set in within a week or so, due to the large sleep reduction. An extreme adaptation is then required to reach the equilibrium of SWS and REM in all sleep blocks to be able to adapt. As with Uberman, any noticeable oversleeps will be devastating to the adaptation, which relies on the careful management of homeostatic pressure.

==Difficulty ==

==Difficulty==

Mostly because of E4's incredible difficulty, successful adaptations are very rare up to date, even though there is a minor amount of success. It is regarded as a superhuman compromise between the sustainable/somewhat friendly [[E3]] and the extreme [[Uberman]]. Because of the near impossibility for an average polyphasic sleeper to adapt to this schedule, it is advised that '''inexperienced or non-mutant sleepers should not attempt this schedule'''.  

Successful adaptations are very rare. The schedule represents a compromise between the relatively friendly [[E3]] and the more extreme [[Uberman]]. Because of the great difficulty, inexperienced and/or average sleepers should not attempt this schedule.  

==Lifestyle Considerations ==

==Lifestyle Considerations==

With 5 sleep blocks per day, even though E4 offers an amazing amount of sleep reduction, sleeping 5 times per day may be a concept that creates boredom and lack of motivation to micromanage that many sleep blocks. This is one of the reasons E4, whether extended or not, is far from being as popular and well-known as E3.  

With 5 sleep blocks per day, E4 is a difficult schedule to fit in to most people's lives. This is one of the reasons E4, including the [[#Extended|extended variant]], is far from being as popular and well-known as E3. It can be viewed as a slightly less extreme version of Uberman. For short sleepers, the core addresses the need for the full functioning of the glymphatic system, which is one of the potential health concerns with [[nap only]] schedules.  

Aside from the inflexibility after adaptation, virtually no exercise and/or consuming alcoholic beverages or drinks for an average sleeper, E4 actually has some saving graces from the more awkward E5, and may be worth an attempt.  

Some have attempted the schedule in order to learn napping skills, without the goal of adapting. As the schedule contains a core, it is much more sustainable than attempting Uberman or [[Naptation]] for the same purpose, allowing more time for the body to get used to the napping pattern.

*First, it is '''less extreme than Uberman''', and the extended variant shows that it remains a viable option for long-term sustenance. Those who vacillate between Uberman's extreme adaptation and E3 (whose sleep reduction does not suffice) can consider E4. The higher frequency of naps (at least on extended version) can help prevent crashes and experienced sleepers can take advantage of their strong napping skills to learn to fall asleep and achieve SOREM in the nap(s) in the early adaptation stage.

E4 can also be used as an emergency schedule for brief periods in an effort to gain time, especially for those who are on schedules with naps. The naps improve alertness and avoids the effects of total sleep deprivation. Alternatively, highly motivated people under great time stress, such as new parents, students, or entrepreneurs, may be able to sustain the schedule for some time, possibly reaching a near-adaptation state. Still, for normal sleepers, any time spent on the schedule can incur sleep deprivation, and is unlikely to be healthy.  

 

*Second, its '''multiple naps''' teaches napping skills quickly, as [[sleep pressure]] racks up fast on E4. This is also an advantage that can push adaptation to a later stage faster than on schedules like [[E1]], as there are multiple opportunities per day to learn to fall asleep and wake up in just 20 minutes. For emergency circumstances that require less sleep for a brief period of time (e.g, ~1 week to ~1 month), the short naps and the core can act as temporary tanks to give some rest rather than pulling all-nighters. Individuals who can take advantage of E4 can be <u>new parents</u>, <u>students on borrowed time</u> or have been used to [[wikipedia:Sleep_deprivation|sleep deprivation]] to power through some amount of days before recovering. The naps only last for 20m, and coupled with E4's total sleep, it can feel like "no sleep" or only "1.5h sleep" for the whole day. It is necessary to ensure that all waking hours are optimized for these urgent activities. Personal motivation and adrenaline will play a massive role to ensure that productivity can be sustained during these burst periods.

*Lastly, E4's scheduling structure gives it the '''same vantage points''' as schedules with 2 daytime naps (e.g, [[DC2]], E3). At face values, scheduling 2 naps during the day can be problematic for a lot of people, but it can be done with the proper scheduling. This can be seen in the noon nap of E4, which can be scheduled during a lunch break, and the fourth nap can be scheduled after work. Breakfast can be done after the second nap, lunch can be scheduled after the noon nap, and dinner after the last nap, or ~2.5-3h before the core. Thus, it can fit into even mainstream '''9-to-5 jobs''', as long as napping is permitted and thoroughly discussed among parties.

*Lastly, E4's scheduling structure gives it the '''same vantage points''' as schedules with 2 daytime naps (e.g, [[DC2]], E3). At face values, scheduling 2 naps during the day can be problematic for a lot of people, but it can be done with the proper scheduling. This can be seen in the noon nap of E4, which can be scheduled during a lunch break, and the fourth nap can be scheduled after work. Breakfast can be done after the second nap, lunch can be scheduled after the noon nap, and dinner after the last nap, or ~2.5-3h before the core. Thus, it can fit into even mainstream '''9-to-5 jobs''', as long as napping is permitted and thoroughly discussed among parties.