Adaptation Stages & Success

After starting a new sleep schedule, some time is necessary for the body to adapt. In general, the complete adaptation usually takes over four weeks. This also greatly depends on schedule, adherence and will vary from person to person. The whole adaptation process consists roughly of four main stages with 6-10 days apiece.

Adaptation is a gradual process, and improvements in sleep deprivation symptoms will become visible as one adheres to their schedule. Furthermore, this will be especially noticeable in individuals new to polyphasic sleep.

Adaptation Stages

First stage

The first adaptation stage is without doubts the easiest. However, it is also where overconfident individuals mistake for a complete adaptation. Stage one contains the following characteristics:

  • Assuming you have not changed the start of your SWS core, falling asleep should be easy during this stage. However, falling asleep during naps can likely be tricky with no prior napping experience.
  • Sleep quality is going to be the same as that on monophasic sleep. The repartitioning process has yet to begin. Cycle compression remains dormant, so the sleep cycle duration is still the same (~90m per cycle, presumably).
  • Throughout this time, you might get a glimpse of what it feels like post-adaptation, as long as you start the adaptation without prior sleep debts.
  • You can also enjoy this stage as it lasts. Your productivity and performance levels should not suffer as you gain some extra hours per day to carry on your usual tasks. 

However, this stage gets shorter on extreme schedules with a low total sleep.

Second stage

Entering stage 2 suggests another step into the overall polyphasic sleep adaptation. This stage has the following characteristics:

  • It is common to start feeling tired during the day for some periods of time.
  • Waking up becomes harder, as total sleep reduces.
  • The feeling of sleepiness becomes more apparent as sleep debt accumulates.
  • Falling asleep generally becomes much easier in many nap(s) and core(s).
  • Random waves of sudden tiredness start surfacing during the day, until they eventually align with the scheduled sleep times.

Similar to the first stage, this stage lasts for a shorter period of time in more difficult schedules.

Third stage

The third stage is the most problematic stage where a substantial amount of people fail their adaptations. Sleep debt has accumulated enough to cause oversleeps. It is thus extremely important to set appropriate alarms ahead of time to minimize oversleeping chances.

The difficulty of this adaptation stage greatly depends on the total sleep reduction. As a result, more extreme schedules are going to be significantly harder. In addition, this stage becomes progressively longer on more extreme schedules.

Important: Read more about handling sleep deprivation, oversleeps, and microsleeps here.

Aside from being the most difficult adaptation stage, Stage 3 also consists of the following trickery and surprises:

  • Many people improved their ability to remember dreams in the naps or cores.
  • Falling asleep can become hard for some sleep blocks. However, this is largely due to the realignment of BRACs and patterns of tiredness dips, etc. 
  • Some sleep blocks may be easy to handle than others, such as short naps. Nevertheless, it is still a challenge to wake up from these sleep blocks.
  • This stage also foresees gradual improvements in sleep habits as the body gets used to the new sleeping schedule.
  • Sleep efficiency also enhances, but the tiredness does not drop and only peaks at the end of this stage.
  • Random premature wakes are common, but they should subside eventually.
  • Sleep debt repayment also begins during this stage. However, undersleeping via skipping naps and cores will only drag this stage out!

Some observations suggest that the sleep stages become more stable during naps and cores. In addition, the sleep cycle duration can also shorten. These are the key improvements in sleep efficiency that make reduced sleep possible on a polyphasic schedule.

If you consistently wake up naturally before the alarm goes off, adjust your alarm clocks accordingly.

Fourth stage

Provided you get this far without significant oversleeping, you should reach this stage. This is the last stage before a polyphasic adaptation is complete. However, it should not in any way be underestimated. Below are its typical traits.

Typical Stage 4
  • Gradual improvements are more common across the board as time goes on.
  • People often start to experience natural wakes before the alarm rings, have more vivid dreams and fall asleep easily.
  • Waking up becomes easier, and alertness improves during the day. Feelings of tiredness will rise sharply before nap times, but you will feel fresh again upon waking up.
  • The patterns of tiredness and energy dips become recognizable, but do not go away entirely. There will be certain hours in the day that you still feel a noticeable drop in performance and focus. For example, early morning hours may be the last to stay as every other hour in the day becomes easy to handle. 

However, this stage can take a very long time to complete. Compared to stage 3, there is a clear drop in tiredness, almost like returning to stage 2. Most importantly, undersleeping during this stage might resurrect stage 3 for a while, as this is also a stage where sleep debt repayment is ongoing. Some people can occasionally experience stage 4 symptoms during previous stages.

It is important to not mistake them for signs of a complete adaptation. It can lead to oversleeping if you underestimate the current level of sleep deprivation.

Fast adaptations

In the past, some people have suggested it might be possible to adapt to extreme schedules such as Uberman in a short time span of only two weeks weeks. According to them, most sleep deprivation symptoms would disappear after only one week.

In reality, this seems like a very atypical experience as most people oversleep during the first week. Those who last do not experience signs of improvements after the 7 days.

  • On more radical schedules, it is common to experience extreme ups and downs in alertness and sleepiness.
  • These can give a false temporary sense of adaptation, which commonly ends with a giant crash as extreme sleepiness returns.
  • This is common during day 5-10 on these schedules, and this is where the actual hard part starts. Thus, the idea of being adapted in one week is fanciful.
  • In fact, extreme schedules like Uberman and Dymaxion are more likely to require at least 3 weeks of persistence before sleep deprivation symptoms start to dissipate.

It is debatable whether adaptation to these extreme schedules is even possible for the vast majority of people. It would require 120 minutes of total sleep to account for 90 minutes of both REM and SWS apiece, not even considering light sleep.

Whether the body switches over to a ‘deeper’ form of SWS and REM sleep to account for this is yet to be shown. These theoretically deeper forms manifest an increase in REM density or delta waves power in SWS.

Some people reportedly have been able to stick to these schedules for a long time, but it has eventually led them to massive oversleeps of several hours. These extended sleep sessions are also detrimental to the adaptation progress. Thus, it is unclear if extreme schedules leave long-lasting damages.

Successful Adaptation Criteria

These are signs to recognize when you have adapted to a schedule in order of decreasing importance:

  • Feel energized and productive when awake. This means there is no need to resort to physical means to stay awake and fuel performance. No memory loss. Elevation in mood and good appetite.
  • Wake up feeling refreshed whether from the nap or the core. Little to no sleep inertia. No desire to return to sleep. 
  • Fall asleep quickly in all sleep blocks, even if you don’t prepare a lot of time to cool down and sleep.
  • Wake naturally without the need for alarms for all sleep blocks. However, this requires long entrainment with a sleep cycle; it often takes months or even years to fully acquire this ability. In the meantime, natural wakes can start to frequent certain sleep blocks, such as naps.
  • You might also remember more dreams from your sleep, even vivid dreams. These dreams can come from the end of your core sleep, or right after sleep onset. Some people remember fewer dreams, however. They consistently wake from light sleep as part of an adaptation to rigid sleep times. Moreover, the naps feel long and drawn out. Each nap can feel like up to 2 hours have passed in just a single 20 minute nap.

Previously, many thought it is possible to adapt within a very short amount of time. This is because remembering dreams in the naps was the sole requirement for success. Via gradual adaptation, recalling dreams from naps does not take long to achieve. However, the core will still have to be repartitioned. Thus, dreams alone do not suffice. 

On more extreme schedules, it is also common to experience all of these adapted signs before a successful adaptation. The difference is that they often do not last. In addition, these schedules are notorious for rapid swings in tiredness. As a result, unsuspecting individuals, who mislabel the temporary signs for a successful adaptation, often fail when they get caught off guard by these tiredness waves.

Beyond Four Adaptation Stages

Recently, the community has proposed that adaptation is a very nuanced concept. Therefore, there are actually two more adaptation stages!

Refer to the following post for more information.


While forcing your body to go through the whole adaptation, you have to take time to understand your body better. Everyone has their own challenges to overcome; while many first-time polyphasic sleepers fail, it is important to learn from that experience and try again. This article cannot prepare you for what your individual adaptation will feel like.

Compiling the general understanding of the ins and outs of adaptation and the support of the polyphasic community and you will go the distance. Log your experience, compare with others logs and develop your sleep-deprivation coping skills.

There are people who have gone through the same process and are willing to help you on the road. Their experience is the basis for the Adaptation Methods article and you can always reach them on our social platforms. Good luck!

Main author: Crimson

Page last updated: 25 December 2020