Oversleep syndrome

From Polyphasic Sleep Wiki

Oversleep syndrome (OSS, alternatively "Oversleeping syndrome") is when a sleeper trying to adapt to a polyphasic schedule keeps oversleeping uncontrollably. This syndrome is often reached after a long adaptation and after sleep deprivation reaches unmanageable levels.


Someone with oversleep syndrome keeps oversleeping while trying to adapt, while claiming that this will stop and they'll be able to adapt eventually. It can manifest itself in different ways, such as falling asleep early, failing to wake up, or falling asleep at random times during the day. Overall, they gain significant amounts of extra sleep time every day to reduce sleep deprivation.

This symptom is fatal for adaptation (to reducing schedules) for two reasons. First, oversleeping ruins compression and repartitioning required for a successful adaptation. With extra sleep time, the body reduces the level of compression, making it impossible to sustain the schedule without oversleeps.

Secondly, oversleeping disrupts the adaptation process as the body is sometimes asleep when supposed to be awake. This also destabilises the circadian rhythm as the dark period and other physiological processes also gets affected by the random oversleeps.


Sub-threshold schedule

This syndrome is often reported by people trying extreme schedules, especially nap only schedules such as Uberman and Dymaxion. This occurs because when the body is completely unable to gain the vital sleep (in this case especially SWS) it needs, it desperately tries anything it can to gain more sleep time. This can manifest in zombie mode, in which a sleeper gets up to turn off the alarms, or do whatever else is necessary, only to go back to sleep and having no recollection of what happened afterwards. People experiencing this often are advised to stop the attempt and recover from sleep deprivation.

Alarm tolerance / Snoozing

It is also possible to experience this syndrome on more forgiving schedules, through a combination of poor alarm use, mistakes, and mild sleep deprivation. Some people (including monophasic sleepers) often turn off alarms repeatedly when trying to wake up, in the hopes that they will be more rested after it. This is extremely detrimental for adapting to reducing polyphasic sleep schedules, as you will only go back to sleep more and more times as sleep deprivation builds up, making adaptation impossible. The brain can quickly learn to disable the alarms unconsciously, which causes you to lose control of your waking time. With the great amount of sleep deprivation built up on some schedules, it is also possible to condition your brain to sleep through the alarm without even attempting to turn it off. Any of these happening would be fatal to your adaptation.


Over long periods, oversleep syndrome causes a sleeper's schedule to become Random. This has been shown to be bad for one's long term health[1], possibly causing lasting damage. Possible (speculated) effects might include:

  • Inability to stay or fall asleep at consistent times
  • Random tiredness throughout the day
  • Impaired ability to gain SWS or REM (lowered overall sleep quality)


The solution to get out of this cycle is recovery. Recovery is when one sleeps as much as required to pay off sleep debt, which can take up to a few weeks to complete. It is also recommended to go without alarms during the process, if at all possible, in order to reduce the habituation to the alarm sounds. Recovery is usually done with a monophasic schedule, but using a Biphasic schedule like E1, Siesta, or Segmented has also been done and should also be possible. For those schedules, the night core should not have an alarm (for Segmented, C2), but it should still be used for the daytime sleep to prevent it from lengthening too much and creating irregular sleep schedules.


  1. Huang T, Redline S (May 2019). "Cross-sectional and Prospective Associations of Actigraphy-Assessed Sleep Regularity With Metabolic Abnormalities: The Multi-Ethnic Study of Atherosclerosis". Diabetes Care. doi:10.2337/dc19-0596.