A Method to Sleep Polyphasically Without Alarm Clocks


Sleeping without alarm may be magic on polyphasic schedules. However, the matter remains unclear at large. The following information in this blog post contains a lot of interpretations from established polyphasic-related studies as well as anecdotal evidence from the community. However, there is discrepancy in some areas of information, so read through the blog with some grain of salt.

Questions and queries

One important question is whether it is possible to sleep without alarm clocks while on a polyphasic schedule and successfully adapt. With all the analysis of the mechanics of cortisol secretion pattern and cortisol awakening response (CAR), it then becomes necessary to pose a question:

  • Can polyphasic sleepers manipulate cortisol secretion mechanics to help prevent oversleeping during adaptation?
  • Furthermore, can they sleep without alarms during and after the adaptation phase?

To answer these questions, cortisol might not be a sufficient method to “will” oneself to wake up around the time alarm goes off or any time they want. Sleep duration should not matter in this equation, either. And to what extent can sleepers abuse this mechanic requires more research on certain bodily processes that dictate sleep-wake control under polyphasic sleeping conditions.


  1. Theoretical Model
  2. Example
  3. Extreme Polyphasic Schedules
    1. Summary of Findings
    2. Interpretations
    3. Downsides
    4. Community Usage Stats

The theoretical model of self-controlling awakening time

The method to pull this off, which is applicable to any sleep patterns, goes as follows:

  • Create a simulation of what desired wake time in the next sleep/day would be.
  • This is possible with natural factors. Examples include worrying about big assignments, projects, job prospects.
  • Artificial factors (e.g, visualize the desired wake-up time a couple minutes before drifting into sleep) are also helpful.
  • Certain research articles have confirmed that stressful factors (e.g, stress and worry) can affect awakening time in the morning, based on monophasic sleep.
  • It is also smart to use one or several alarm clocks to aid in polyphasic adaptation to remain on the safe side.

One study pointed out that work overload and chronic worrying cause huge differences in CAR levels during weekdays and weekends.

  • Participants who were able to sleep longer only had a slight increase in CAR upon awakening.
  • Those who slept less had a sharper increase in CAR1.

This result is reasonable because stress from these personal concerns lower sleep quality, resulting in multiple sleep issues like disrupted sleep2,3. As a result, stressors may decrease the percentage of vital sleep stages and increase light sleep.

  • Another study suggested that cortisol secretion during morning hours is significantly higher than afternoon hours in healthy young and old adults4.
  • An explanation is that the adrenal glands are more sensitive to adrenocorticotropic hormone (ACTH) in the morning; this is consistent with the previously cited studies on how timing of the circadian rhythm can affect cortisol secretion amount.

A practical example in the community


05/03/20 Biphasic-x Day 11

Core: 23:00 – 05:43

No alarm, shorter core, 6h43m. Feeling pretty good actually, no inertia.

Nap: 16:02 – 16:59

No alarm, fell asleep quickly once again. Apparently I have napping talent? xd. Longer nap, 57m. Feeling refreshed.

TST: 7h40m

Today was a little different. I was feeling a bit stressed about the essay I had to write in class today. Thus, I wanted to see if I could wake up early without an alarm to prepare for the essay. I decided to attempt the “internal alarm clock technique” that General mentioned and did in his Biphasic-x logs.

I visualized waking up after 7h (so at 6 AM) as I fell asleep. Surprisingly, it actually worked! I woke up after 6h43m, a little short of 7h, and I spent my morning studying. After school, I took the nap a little earlier than usual. Because my core had shortened, the nap was longer, kind of like a siesta.

My alertness during the day wasn’t any different than normal. This is really promising; this Biphasic-x has crazy potential; I look forward to explore it further.

TST was a little shorter today, so we’ll see if anything changes. I predict that I’ll sleep a little longer tomorrow as a sort of “recovery”.

Weaver (16), reported from the Discord.

Weaver’s flexible Biphasic-X

Further questions

The biphasic sleeper in the community has completed the scenario successfully. His schedule is a non-reducing biphasic pattern. The sleeper did not use any extra alarm clocks to facilitate awakening at the desired waking hour and pulled it off effortlessly. This was also the first intentional attempt at using a “stress response” to ease waking up. Subjectively, it was a good awakening with no sleep inertia.

However, there are many questions related to the procedure:

  • Is this a healthy way to sleep when stress is necessary to induce wake-up time?
  • What about other polyphasic schedules with shorter core sleep(s) and multiple naps? Does this technique work on naps and shorter sleeps?
  • Is it only cortisol or there are some other hidden processes that facilitate a refreshing wake for said polyphasic sleeper?
  • Can we attempt this everyday to help adapt to a polyphasic schedule?
  • What happens to cortisol levels during the whole time?
  • Is there any reduction in REM sleep duration near the end of the core because of an earlier wake time?

Cortisol explanation

These are some possible questions one would ask, because sleeping in a stressful environment is not healthy1. Though in the case of Weaver, he did not use this technique in the nap; instead, he napped until he woke up naturally.

  • Speculatively, cortisol levels rose sooner than usual to set Weaver’s earlier wake time. This is also consistent with the study on the difference between weekdays and weekends’ CAR1.
  • However, while this mind trick has worked on non-reducing biphasic schedules anecdotally, the same is inconclusive for other reducing polyphasic schedules.
  • Moreover, it is doubtful whether everyone should use this technique frequently to wake up by tapping into the stress-response system.

A well-established circadian rhythm cue, light, can cause an elevation in CAR intensity in the morning5,6.

  • At first sight, one would predict that setting up artificial blue light in the morning can ease the awakening process7.
  • Aside from artificial blue light, the natural source of light from dawn time in the local area can help increase the level of cortisol in the body some time before awakening. This can potentially be useful for certain scheduling options. Examples include Dual Core sleep with a morning core, Everyman sleep with a REM peak nap.

More extreme polyphasic schedules

Will the cortisol mind trick work on non-biphasic schedules? The answer is indeterminate.

Summary of findings

From the some polyphasic-related studies on CAR, these are some notable points:

  • Short naps and late naps in the day (afternoon/evening time) do not trigger cortisol release prior to awakening. This is especially if those contain only light sleep or brief SWS3,5,8. However, there are potentially exceptions in repartitioned REM naps close to morning hours.
  • Sleep blocks full of REM appear to be coincidental with CAR and cortisol increase after the morning wake. This idea suggests that there is a strong relationship between morning and cortisol release, regardless of sleep patterns5,8.
  • Longer sleep sessions during the day (morning/early afternoon) consistently generate CARs5,8.

Possible Interpretations

General Observations

  • Short naps do not seem to trigger CAR. This is parallel to the first couple days of adaptation where light sleep percentage is high. Thus, using the trick here will be pointless. Sleep quality will not be “efficient” yet; waking up is easy on its own thanks to a high percentage of light sleep in each sleep block.
  • When the adaptation progresses into tough periods, the cortisol trick may or may not be effective at all.
  1. Zombie mode can shut down willpower and human supervision would often be mandatory to sustain an extreme polyphasic pattern (e.g, Uberman).
  2. When sleep deprivation starts kicking in after a couple nights of sleep deprivation, certain studies have shown that cortisol levels might be hindered upon morning awakening. They instead build up in the evening4,9,. This complicates the mind trick where it is impossible to manipulate cortisol level by the time a sleep session ends.
  • In fact, no studies so far can directly elucidate how humans can use their subconscious mind to facilitate waking up whenever they want.

More split & extreme polyphasic schedules

Can all REM or SWS naps release cortisol upon awakening, especially after adaptation is complete? The answer is also inconclusive.

There was a Uberman study with 1 subject lasting for 5 weeks without cognitive impairment after the study; there was also no change in his cortisol secretion pattern10.

  • This suggests that the body is forced to adapt to a new sleeping regime while retaining the circadian rhythm as on a monophasic schedule.
  • The REM peak nap on Uberman is likely to cause a CAR, since it was similar to the CAR on monophasic sleep (morning time). However, the sample size was too small (1 subject) and 5 weeks might not be enough to completely change the cortisol secretion pattern.
  • The outcome is also consistent with a polyphasic study where circadian rhythm of 24-hour cortisol secretion is very resistant to change5.
  • Thus, as of now, REM naps around dawn on a polyphasic schedule can produce CAR instances consistently. However, it is uncertain if REM naps around noon or afternoon are capable of the same.
  • At the same time, a sleep block full of SWS may or may not produce any CAR occurrences; it is less likely for SWS sleep blocks to achieve the same as REM sleep blocks. From the aforementioned studies, SWS suppresses cortisol secretion.


  • Overthinking or overvisualizing about waking up at a specific time may increase sleep onset latency. This is because of wandering thoughts that keep the mind active rather than preparing the brain for the slow-wave state.
  • This state of daydreaming can affect the sleep quality of all sleep blocks, regardless of a core or a nap.
  • Stress will continually build up with more accumulated sleep deprivation, which is bound to wreck alertness and productivity.

Community usage stats

Anecdotally, so far, the cortisol trick is not common. Not in a sense that adapted polyphasic sleepers (on Everyman tier) have reported to make the adaptation process easier. Thus, when adaptation is complete, there is even less of a reason for them to resort to this trick. This is because they have been familiar with the designed sleep-wake hours on their own schedules.

It also becomes common that these sleepers are able to wake up on their own even around the 20-minute mark of a nap or earlier. The same thing may even happen in a core sleep. However, the same premature wakes remain unverified for nap-only schedules due to their absurd sleep reduction.

  • In polyphasic schedules with at least some kind of core sleep, sleepers still use alarm clocks post-adaptation. However, they are more of a back-up measure. Oversleeping does not usually happen by that point with normal sleep hygiene practice. This is except conditions that result in an increased sleep need like intense exercising, drinking, overeating and sickness.
  • After the adaptation period, these sleepers sometimes even wake up briefly before the alarm goes off. Consistent anecdotal reports hint that CAR instances stabilize and possibly activate earlier before awakening.

Thus, when the adaptation is complete, the cortisol trick is not necessary anymore; the body has become accustomed to the new sleep pattern.


The nature of CAR generation when there are changes in sleep architecture is complicated. Thus, currently, it is not conclusive how this trick can be used to wake the body up by the scheduled awakening time on a polyphasic schedule. It is also largely unknown how potent the CAR trick is without alarm.

The seemingly common successes on biphasic schedules (mainly in the non-reducing form) suggest that CAR can be a tool to avoid oversleeping. It may help sustain a polyphasic schedule during adaptation. However, this is limited to some polyphasic schedules with a core sleep, alongside the assistance of alarm clocks. There are also certain risks with the CAR trick; thus, polyphasic sleepers should be cautious of incorporating this strategy.

Main author: GeneralNguyen
Page last updated: 2 April 2021


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