From Polyphasic Sleep Wiki

Triphasic is the original and most commonly known schedule in the Tri Core family, which consists of only 3 core sleeps and no naps. <translate>

Tri Core 0
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Total sleep4 hours 30 minutes
Proposed byLeif Weaver
DifficultyVery hard
Specification3 single-cycle core sleeps



Leif Weaver, the first polyphasic sleeper with a successful adaptation to Triphasic, remained on the schedule for several months. This schedule was known to be equidistantly scheduled, with a 6.5h wake gap between each core sleep. Because of the structure, Triphasic can be considered a more extreme Segmented schedule, with a long siesta. Despite the origin of the schedule, equidistant sleep is not required, although no more than 8h wake gap between any core sleep is recommended. For the daytime core and with the recorded successes in Triphasic (except Triphasic-extended), it is possible to stay awake for up to 9 hours from the daytime core to the core around SWS peak hours, while the wake gap between the 2 other cores around night hours tends to be smaller.

Because of the distribution of Triphasic sleep, it also possesses characteristics of Dual Core sleep, where the evening core favors SWS, the sunrise core favors REM sleep and the daytime core contains mixed sleep stages.


When adaptation first begins, SWS will resume in all core sleeps as the normal flow of a normal sleep cycle, where light sleep begins, then SWS continues and then finally REM sleep finishes the cycle. In the second core, SWS pressure may be weaker than REM pressure, allowing for some REM sleep to get in this core. However, as adaptation progresses, both SWS and REM deprivation symptoms are likely to manifest because of the extreme repartitioning of these vital sleep stages into each core sleep to follow the homeostatic and circadian pressures. This will make the first core very difficult to wake from, because of prevalent SWS wakes, which was reported to result in oversleep until the second core. During the whole adaptation, the daytime core is likely the easiest to handle, and can shorten to as low as 60m after adaptation. Because of the high repartitioning of sleep stages on merely 4.5h total sleep, Triphasic offers a lot of sleep reduction along with a high level of sleep compression.


Aside from the non-equidistant Triphasic scheduling which has proven to be viable by a couple sleepers, the most popular and widely successful version is the extended version.


Sample Triphasic-extended

Because of the major difficulty posed by the SWS core during adaptation, this extended version allows more room for SWS in the first core, with a higher chance to avoid many SWS wakes during adaptation. This also bumps the total sleep time to 6h, which is considered a beginner-friendly sleep total. Alongside a much easier adaptation, the wake gap from the REM core to the afternoon core can be expanded all the way to ~11h wake gap (1 reported success). This versatility greatly boosts the viability of Triphasic-extended or schedules with a daytime core.

A few polyphasic sleepers have been able to adapt to a Triphasic-extended variant with a 9-10h wake gap from morning to afternoon. The ability to schedule this distribution of sleep aids in daily scheduling, in which the daytime core can be moved to ~4 or 5 PM. With an overall easier adaptation than regular Triphasic, the night time hours between 2 nocturnal cores can be utilized for various activities without having to sacrifice all productivity when adapting. Another bonus from Triphasic-extended is that the first core can begin at late evening hours, around 11 or 11:30 PM without too much hassle, thanks to the increased total sleep. The core extension also suits individuals with somewhat high sleep requirements, while an adaptation to the regular Triphasic can become unsustainable.

Alternatively, it may be possible to extend the REM core to 3h instead of the SWS core in the evening, which may be beneficial for social hours in the evening or less sleep in the early evening hours. However, it has no known official successes to date. Although it is worth noting that a sleeper with low SWS needs and high REM needs may benefit from this Triphasic-extended variant.


Non-reducing Triphasic

Non-reducing Triphasic is rarely ever attempted, but recently there have been some attempts, mostly from underage population. It is unclear what the advantages would be with such a bulky and seemingly cumbersome sleep distribution, compared to Triphasic-extended. Success rate is also very rare, only a case or two. The adaptation is potentially even easier than Triphasic-extended, but this variant is only for short-term, or those who cannot in any way sleep in one long chunk at night. The niches are very small, and despite a lot of sleep, it may not be totally friendly to underage individuals, who are better with a non-reducing biphasic pattern instead.

Lifestyle consideration

Because of Triphasic's evening core sleep and daytime core sleep at socially inconvenient hours, Triphasic and Tri Core schedules overall are very unpopular. The requirement to have a core in SWS peak (especially on regular Triphasic) makes it necessary to forfeit social life around evening hours. Another downside to Triphasic is that 4.5h total sleep is not sufficient to make it very flexible after adaptation. So far, there have only been 1 or 2 known adapted cases of being able to make a Triphasic core flexible by no more than 30m. With the limited flexibility for an average sleeper (with normal sleep needs), it is very challenging to sustain Triphasic long-term, even if the adaptation phase can be completed. Lastly, intense exercising may not be totally supported by Triphasic, because increasing SWS requirements for recovery can prove to be very difficult to avoid SWS wakes in any cores. However, staying on Triphasic can create a sense of very long days, with a long wake gap between each core.

However, Triphasic-extended has a whole lot more utility baked into it. The first core can be scheduled late (around 11 PM or later) makes it easier to sustain social life in the evening. More sleep also allows for more physical training, and flexibility after adaptation. Triphasic-extended has great viability in becoming flexible, and can recover from a lot of damages and disruptions from daily life events. The long, uninterrupted morning-afternoon wake gap is often capitalized on by adapted sleepers, with the opportunity to fully commit to different events without having to worry about sleep time. Triphasic-extended is one of the most well-rounded schedules in stock, and has reported a lot of successes. A lot can be achieved on this schedule with only 6h of sleep each day.