This is a continuation of Scheduling Introduction in case none of the standard sleep schedules suit your needs. Some concepts proposed here are more advanced and some can be a bit more experimental with some (but minimal) evidence of validity. Nevertheless, it is worth considering this section when designing a schedule.
Strongly rotate your circadian rhythm
The more the sleep schedule is moved with respect to the local day-night cycle, the less likely it is to overlap with the optimal times for the individual sleep blocks. This can become problematic due to insufficient sleep which in turn leads to chronic tiredness. This can be avoided by moving circadian rhythm along with your sleep schedule by using various circadian cues such as light, food, activity or even temperature (see Lifestyle considerations). The longer the relative shift and the shorter the total amount of sleep, the more cues are need to be monitored to ensure a healthy circadian rhythm. Light management should always take place regardless if the schedule is shifted or not.
It is highly advised for people to use this as a last resort or if they have significant difficulty sleeping earlier, e.g. during SWS peak, for example from working on a 3rd shift job.
Flexible nap timing
Flexible nap timing (often shortened to just flexing) is defined as moving sleep times from day to day, without changing target sleep lengths. Sustaining a flexible schedule requires adapting to a rigid base schedule first with strict sleep times. The community has found that a full adaptation to a schedule is required, ideally for several weeks or more before starting to flex. After this is done, it is possible to attempt to gradually move sleeping times of one or more sleeps, from day to day.
Depending on the total amount of sleep scheduled, flexing may require adding 30 or 90 minutes to a core, to buffer the reduced sleep efficiency of flexed sleep. This is particularly a problem with schedules with a very low total sleep times, such as Everyman 3 for example.
Very experienced polyphasic sleepers who have already adapted to a polyphasic schedule and then flexed the sleep times successfully in the past might be able to flex times slightly during new adaptations. If they are unable to do so, they will likely be able to start flexing nearly immediately after the new adaptation is complete, as opposed to beginners who often require more time to adapt.
Most standard schedules suggest the nap lengths to be 20 minutes long. However, scheduling a 20 minute nap into two 15 minute naps is also possible. The naps should not be taken within at least 2 (preferably 3) hours away from any other naps.
15 minute naps are especially beneficial if there are scheduling difficulties present preventing the ability to reliably take a 20 minute nap, but where 15 minute ones are possible. For example if someone has a 20 minute work break and needs to nap in their car but the travel time back and forth is a few minutes each way.
Some people might find that they wake up naturally after around 10 to 15 minutes into a nap. The advantage for getting up at this point in time is the lack of sleep inertia, but the amount of REM sleep gained from the nap is smaller as a cost. These people will often find that if they start getting up at this time they need to schedule additional naps in order to adapt due to the decreased amount of REM sleep gained from the shorter naps. The option to sleep in and finishing the nap at 20 minutes is often also possible.
The reason why one 20 minute nap can’t be split into two 10 minute ones is because some time is spent in light sleep at the beginning of every nap. In order to make up for this time, an additional 5 minutes is added to gain the same total amount of REM sleep as one 20 minute nap.
Protracted Naps (Pronaps)
The idea behind Pronaps is that napping at the right time of the day for longer than the usual 20 minutes can be done while still maintaining REM sleep and avoiding sleep inertia. Originally published on Polyphasic Society, those authors suggested a longer first nap of 40m for people on Everyman 3 who felt they have greater sleep need.
On the Polyphasic Discord, user Jelte1234 independently suggested and further developed the idea as a 35-45m nap for any schedule that has a nap in the 6-9AM REM peak, and has a core of at least 2 cycles in the SWS peak.
If a nap is longer than 20 minutes there is usually a high likelihood of entering SWS, which leads to rough wakes and possible oversleeps, and is thus to be avoided. By placing a nap in the REM peak (usually around 6 to 9AM in the morning) the chance to enter SWS is greatly reduced. Because of this the nap can be allowed to be longer, which enables the opportuníty for more REM to be gained from a single nap. In order to minimize SWS pressure a Pronap should be combined with a sufficiently long core placed well in the ideal SWS peak. This is to ensure that all the SWS need is taken care of before the Pronap. Alternatively two 20 minute naps could be combined into a single Pronap after adaptation to a polyphasic schedule in order to avoid increasing the SWS pressure, however the specifics of this procedure and the necessary scheduling is unknown.
When to use
The Pronap is most useful on the Everyman line of schedules. Since the Dual core (excluding DC3 and DC4) and Tri core lines of schedules already have a core placed near the REM peak, there is no additional room for a nap to be taken there. Due to SWS pressure considerations, a Pronap is neither suited for E4 or E5, nor for nap-only schedules.
Hypothetical benefits would be ensuring sufficient daily REM, possibly improving the ease of a maximum gap after the first nap (e.g. 8 hours for E2 – yet to be shown), possibly allowing greater schedule flexing ability once adapted, or even removing a later nap. A pronap did however not seem to allow a greater duration of the sleep block after the Pronap than 8 hours on E2 for two users on the Discord who attempted it.
During adaptation, it is possible that some of the time a Pronap will end in an SWS wake. It is important to remember that sleep phases are still being redistributed, and it will sort itself out as you progress through the adaptation.
In cases when the standard schedule names are insufficient for describing the schedule the following scheduling ‘modifications’ can be applied:
- Shortened: The length of a core sleep has been shortened in comparison to the standard schedule by at least one sleep cycle. This greatly increases the difficulty of the schedule and in most cases makes it not sustainable for most people with average sleep needs.
- Extended: The length of a core sleep has been lengthened in comparison to the standard schedule by at least one sleep cycle. This can make the sleep schedule easier, accommodate for people with increased sleep needs (including teenagers), allow for increased flexibility in nap timings after the adaptation and provide adequate recovery for continuous physical exertion (such as substantial exercise/sports every day).
- Flipped: The schedules sleep blocks have been shifted so that the night sleeps are scheduled during the day and vice versa. These variants are typically attempted by people working during the night.
- Modified: A fundamental alteration has been made to the standard schedule. For example a Dual core schedule where the cores are not scheduled to be successively placed. Making fundamental modifications to tested schedules is not recommended for new polyphasers.
- Recovery: Used when someone is recovering from sleep deprivation with the intention to attempt an adaptation again after the sleep deprivation is healed. See Adaptation methods for more information.
These schedule modifiers can be placed after the abbreviated schedule names, for example ‘DC2-shortened’, ‘Mono-recovery’, ‘Siesta-shortened’ and ‘E1-flipped’ to make the schedule name more descriptive and talking about schedules easier. The Polyphasic Sleep Discord server uses this standardized naming system.
Shortened schedules are mostly not sustainable for people with normal sleep needs. Modified schedules should be done with caution, as there are usually reasons why the standard schedules are designed to be the way they are. The other modifications are sustainable for most individuals. Some attention should be paid if a flipped schedule is necessary, as the circadian rhythm will have to be shifted and maintained as such.