Reviewed by Sahil Chopra, MD, and Stacey Gunn, MD.

Research by Savit Malhotra.

With the end of our insomnia series, we will now shift courses and begin a mini-series on napping. In this series, we will take a look at what constitutes a nap, if naps are healthy, the different types of naps, and how to effectively take a nap. 

Introduction

At some point, you’ve probably told yourself that you were only going to close your eyes for a few minutes. And then you woke up two hours later, it was dark outside, your work has piled up, and you felt more tired and groggy than before. Now you’re probably left thinking that the “quick” nap you just took is one of the worst things you could’ve done, and now you have to scramble to make up for the lost time. Sound familiar? Don’t worry, you’re not alone. Most people have likely experienced this to some degree. 

But naps don’t have to be a bad thing and, when done right, they can be an incredibly useful tool for boosting productivity. In this new mini-series, we will be doing an in-depth analysis of naps, discussing both what types of naps there are and how to effectively take a nap. We’ll first start with the science behind napping and answer the fundamental question: Are naps actually good for you?

What is a Nap?

Simply put, a nap is a short period of daytime sleep that is meant to provide some sort of additional sleep to mitigate sleep debt, help boost energy and alertness. Interestingly, there are different types of naps broken down into their lengths. The most common, and arguably the most effective, nap is the “power” nap. This is a short, 10 to 20 minute period of sleep that helps a person boost their productivity during the day.[1] This is the nap that we will be focusing on for the remainder of this article. Aside from this, there is also the coffee nap (or nap-a-chino, which we will be covering in the next article), the prophylactic nap (which is a much longer nap that lasts for 2-3 hours), the fulfillment nap (which is typically for children to help them meet their sleep needs), and the essential nap (which doesn’t have a defined length of time but is instead meant to help the body recover, especially during sickness).[2] However, different people will call different types of naps by different names. Thus, for our purposes, we will divide naps into two categories: short naps (10-20 minutes) and long naps (more than 90 minutes). 

The reason for dividing the naps in this way is that shorter naps tend to be the best for boosting middle-of-the-day productivity, while longer naps tend to take up more time due to the body cycling through the different stages of sleep. Since short naps don’t cycle through the sleep stages, they are easier to wake up from and are less likely to cause sleep inertia (a temporary state of disorientation and declined performance).[3] 

Short Naps

During a short nap, the brain tends to enter the earlier stages of the sleep cycle (stages 1 and 2 of non-REM sleep) without fully crossing into the deeper stages. These earlier stages are the lighter stages during which a person is more easily woken up.[4] During stage 1 of sleep, which only lasts a few minutes, the brain begins to transition from wakefulness to a state of sleep. Additionally, the heart begins to slow, and the muscles begin to relax.[5] Thus, stage 1 helps to prepare the body for rest and, in terms of a nap, helps to get the body ready for stage 2. During stage 2 of sleep, we see many of the benefits of napping begin to take place. Stage 2 of sleep consists of the brain waves slowing down and there being pauses between the bursts of electrical activity happening in the brain.[6] It is during this time where the brain is able to rest and recover. Typically, the first bout of stage 2 of sleep lasts for somewhere between 10-25 minutes before a person starts to enter slow wave sleep.[7]

It is for this reason that nap lengths are recommended to only last for 10-20 minutes. The brain can finish these two stages entirely, and, since these are lighter stages of sleep, a person can easily wake up. While stage 3 of sleep contributes to a further slowing of brain activity, it has been shown that going through stage 2 of sleep while napping contributes to an increase in concentration and alertness while improving motor skills and elevating mood.[7] Additionally, the first two stages of sleep tend to be easier to time, and even if your timing is slightly off, waking up from one of these two stages is not too difficult, and sleep inertia generally occurs while waking up from stage 3 of sleep, or deep sleep, and also while waking during REM.[8] Additionally, one study found that shorter naps tend not to create sleep inertia, whereas longer naps do (we will be doing a more in-depth analysis on this study in the next article).[9]

Long Naps

Typically, one complete sleep cycle lasts between 90 to 110 minutes.[12] Thus, taking longer naps will likely lead to a person going through all stages of sleep (stages 1 and 2, which we previously discussed, and stage 3 and REM sleep). During stage 3 of sleep, we see the body in its deepest stage of sleep. Brain waves slow even more, and the body is able to get the most rest during this stage. However, with it being the deepest stage of sleep, it is also the stage during which a person is hardest to wake up from.[13] Lastly, the body will also go through the REM (rapid eye movement) stage of sleep. During this stage, the eyes move rapidly behind the eyelids (hence the name), and, contrary to the other stages of sleep, the brain is lively and quite active. It is also during this stage that people have vivid dreams.[14]

The problem with taking long naps is that it can be hard to time the individual stages of your sleep. Thus, it is entirely possible that your alarm goes off during stage 3 of sleep. Since it is the deepest stage of sleep, you may either sleep through the alarm altogether or wake up during this stage and create sleep inertia.[8,13] For this reason, it tends to be better to avoid falling into this stage of sleep by minimizing the length of your nap. Alternatively, you can also choose not to set an alarm and let your body naturally go through the sleep stages and wake up on its own. This can help minimize the sleep inertia you may experience.[10] The issue here is that when you have no control over how long you sleep, there is a very good chance that you end up sleeping longer than you would have wanted to. This can increase your chance of facing problems later at night when you try and get proper sleep. You may find it hard to fall asleep or stay asleep, leading to you feeling worse the next day.[11]

Conclusion

Simply put, too much of anything can be bad for you, and naps are no exception. Oftentimes, naps get a bad rap for causing grogginess, losing time during the day, and impacting nighttime rest. However, when done intentionally and timed correctly, naps can be an effective tool that a person can use to improve their mental cognition, restore their energy, and help their mood. Research has agreed that the optimal time for a nap is between 10-20 minutes, and a longer amount of time can cause less than optimal results. 

For this reason, we recommend that those who choose to take naps try to limit their daytime rest to 10-20 minutes. By doing so, a person can wake up feeling refreshed and boost their productivity during the day while attempting to minimize the effect on their nighttime sleep. This being said, a nap should not be a replacement for nighttime sleep. Getting a proper 7-9 hours of rest every night is, for most people, the best way to rest and recharge their body.

‍References

  1. Levi, Rebecca. “What Are the Different Types of Naps?” Sleep Doctor, 22 Jan. 2024, sleepdoctor.com/pages/health/types-of-naps.
  2. Zwarensteyn, Jill. “Types of Naps & Their Benefits.” Sleep Advisor, 21 Aug. 2024, www.sleepadvisor.org/types-of-naps/.
  3. “Module 7. Napping, an Important Fatigue Countermeasure, Sleep Inertia.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 31 Mar. 2020, www.cdc.gov/niosh/work-hour-training-for-nurses/longhours/mod7/03.html#:~:text=After%20awakening%20from%20a%20nap,before%20taking%20a%20short%20nap.
  4. Summer, Jay Vera. “Napping: Benefits and Tips.” Sleep Foundation, 11 Mar. 2024, www.sleepfoundation.org/napping#:~:text=for%20different%20people.-,How%20Sleep%20Works%20During%20Nap%20Time,take%20place%20during%20REM%20sleep.
  5. “What Happens during Sleep?” Eunice Kennedy Shriver National Institute of Child Health and Human Development, U.S. Department of Health and Human Services, 29 Apr. 2019, www.nichd.nih.gov/health/topics/sleep/conditioninfo/what-happens#:~:text=follows:1%2C2-,Stage%201,Your%20body%20releases%20hormones.
  6. professional, Cleveland Clinic medical. “Sleep.” Cleveland Clinic, 23 June 2023, my.clevelandclinic.org/health/body/12148-sleep-basics.
  7. Suni, Eric. “Stages of Sleep: What Happens in a Normal Sleep Cycle?” Sleep Foundation, 21 May 2025, www.sleepfoundation.org/stages-of-sleep.
  8. “Sleep Inertia: What It Is and How to Get Rid of It.” Cleveland Clinic, Cleveland Clinic, 8 July 2024, health.clevelandclinic.org/sleep-inertia.
  9. Brooks, Amber, and Leon Lack. “A brief afternoon nap following nocturnal sleep restriction: Which nap duration is most recuperative?” Sleep, vol. 29, no. 6, 29 June 2006, pp. 831–840, https://doi.org/10.1093/sleep/29.6.831.
  10. Pacheco, Danielle. “Sleep Inertia: How to Combat Morning Grogginess.” Sleep Foundation, 11 Apr. 2024, www.sleepfoundation.org/how-sleep-works/sleep-inertia#:~:text=Sleep%20inertia%20is%20the%20groggy,reaction%20time%20and%20decision%20making.
  11. Aggarwal, Brooke. “The Truth about Napping: How Much Is Too Little or Too Much?” ColumbiaDoctors, 13 Mar. 2025, www.columbiadoctors.org/news/truth-about-napping-how-much-too-little-or-too-much.
  12. Patel, Aakash K. “Physiology, Sleep Stages.” StatPearls [Internet]., U.S. National Library of Medicine, 26 Jan. 2024, www.ncbi.nlm.nih.gov/books/NBK526132/#:~:text=Approximately%2075%25%20of%20sleep%20is,roughly%2090%20to%20110%20minutes.
  13. professional, Cleveland Clinic medical. “Controlled Zzzs.” Cleveland Clinic, 25 Apr. 2025, my.clevelandclinic.org/health/body/12148-sleep-basics.
  14. Summer, Jay Vera. “REM Sleep: What It Is and Why It’s Important.” Sleep Foundation, 22 Mar. 2024, www.sleepfoundation.org/stages-of-sleep/rem-sleep.