Napping is a common practice across many cultures, with roughly 50-60% of adults reporting that they nap at least occasionally. However, there is an ongoing debate around whether these daytime sleeps are beneficial or detrimental to our health and productivity. Proponents argue that napping allows us to recharge our batteries and promotes improved alertness and performance. Critics argue that napping can leave us feeling groggy afterward and disrupt our natural sleep cycles. So what’s the verdict – are naps helpful or harmful? Let’s examine the evidence.
The potential benefits of napping
Improved alertness and performance
Multiple studies have shown that napping can increase alertness and improve performance on cognitive and memory tasks. In one study, participants who took a 60-90 minute nap in the afternoon experienced improved alertness and cognitive performance for up to 10 hours afterwards compared to those who didn’t nap. [1] Similarly, another study found taking 30 minute naps on consecutive days led to cumulative improvements in psychomotor vigilance and working memory over time. [2]
Napping may provide these benefits by allowing us to enter deeper, restorative stages of sleep more rapidly compared to nighttime sleep. The boost in alertness after napping is likely driven by reduced sleep inertia upon awakening during the day. [3]
Increased learning and memory
Napping has also been shown to enhance certain types of memory, including procedural and spatial memory. For example, a 90 minute nap improved performance on a visual perception task compared to remaining awake in one study. [4] Naps may improve memory by allowing our brain to better process and store new information during sleep through neural reactivation and consolidation. [5]
Improved mood
Taking a nap can also put you in a better mood. Studies show that napping is associated with reduced fatigue, anxiety, and improvements in overall mood compared to not napping. [6] One reason for this may be that sleep helps regulate our emotional centers in the brain and allows them to reset after experiencing stress or strong emotions during wakefulness.
Increased creativity
Naps may also boost creativity, likely by promoting divergent thinking and openness to new ideas. In one study, a 60-90 minute nap led to improvements in a creative problem solving task compared to staying awake. [7] The combination of rested focus and associative thinking from napping may stimulate our creative juices.
Possible heart benefits
Emerging research suggests naps may provide some benefits for heart health. One study found that adults who took frequent naps (at least 3 times per week) had a lower risk of heart disease. [8] Other studies show cardiovascular benefits from short naps under 30 minutes. [9] However, more research is still needed to confirm these potential heart-related benefits.
The potential downsides of napping
Sleep inertia
While naps can increase alertness, there is often a period of impaired performance and grogginess immediately after waking up, known as sleep inertia. Symptoms like disorientation, fatigue, and impaired motor dexterity may persist for up to 30 minutes after awakening from a nap. [10] This transitional state can reduce the benefits of napping, particularly for short naps taken during the workday.
Interference with nighttime sleep
Daytime napping may make it harder to fall asleep or stay asleep at night for some people. This can happen by reducing homeostatic sleep pressure during the day so there is less drive for sleep at night. [11] Late day naps are more likely to interfere with nighttime sleep compared to earlier naps. Individuals with insomnia may be more vulnerable to this negative impact.
Grogginess upon waking up
Some people report feeling groggy or tired after taking a nap rather than rejuvenated. This may result from being woken up during deep, slow wave sleep, which can leave you feeling disoriented. Allowing adequate time to fully awaken before resuming activities can help minimize this groggy feeling. The timing and length of naps influences whether you’ll wake up refreshed or drowsy.
Reduced productivity over time
While napping offers immediate benefits, it may reduce productivity over the course of a day. For example, one study found that while a 30 minute nap initially improved alertness and performance, over the span of 10 hours participants who napped were less productive than non-nappers. [12] This suggests strategically timing naps may be better than taking them routinely during work hours.
Increased risk of some health conditions
Frequent and lengthy daytime napping has been linked with a higher risk for some chronic health conditions. Studies show an association between regular napping and increased risk of type 2 diabetes, heart disease, and all-cause mortality. [13] However, further research is needed to determine if napping directly contributes to development of these conditions.
When are naps most beneficial?
The benefits you’ll get from napping and the likelihood of negative side effects depends heavily on nap timing, length, and individual habits. Here are some nap strategies that can maximize benefits:
Early to mid-afternoon naps
Napping earlier in the day causes less nighttime sleep interference compared to later naps. The post-lunch dip around 1-3pm coincides with a natural circadian low point making it an ideal nap time for many people. Naps as short as 10 minutes during this window can boost alertness and performance.
Limit nap length to 30 minutes
The best nap duration is around 15-30 minutes. This allows you to pass through light sleep into restorative slow wave sleep without entering lengthy periods of deep sleep which can cause sleep inertia upon waking.
Avoid napping after 3pm
Later afternoon and evening naps are more likely to make it hard to fall asleep at night. Limit late naps to 20 minutes max to reduce this effect.
Allow time to recover from sleep inertia before driving or operating machinery
It can take 15 minutes or longer to fully recover cognition and motor coordination after waking up. Be cautious before resuming any safety sensitive activity after a nap.
Experiment to find what works best for you
Responses to napping can vary based on individual characteristics like age, sleep habits, and circadian preferences. Finding your optimal nap schedule may take some trial and error.
Tips for productive napping
If you want to nap in a way that boosts your performance while minimizing adverse effects, consider these tips:
– Stick to naps under 30 minutes during typical circadian dips in alertness (e.g. 1-3pm)
– Avoid napping after late afternoon unless urgently needed for alertness
– Allow 15-30 minutes after waking up before resuming cognitively demanding activities
– Use caffeine strategically to counteract drowsiness after waking up
– Nap in a comfortable, dark and quiet space conducive to sleeping
– Set an alarm to avoid oversleeping
– Try meditating instead if naps aren’t refreshing for you
Who may benefit most from napping?
While most healthy adults can get some benefits from brief daytime naps, they tend to be most advantageous for:
– Shift workers and night owls – Naps can mitigate fatigue related to overnight shifts or staying up late
– Older adults – Naps may counteract age-related declines in sleep quality and circadian rhythms
– Patients with certain conditions – Napping helps combat excessive daytime sleepiness in disorders like sleep apnea or narcolepsy
– Athletes and highly active people – Naps can aid muscle recovery after intense training sessions
– People recovering from sleep deprivation or jet lag – Napping accelerates recovery from acute sleep loss
Some evidence also suggests that frequent nappers may get more benefits from continuing to nap compared to occasional nappers.
Conclusion
Overall, research suggests that short, well-timed naps generally provide more benefits than drawbacks for healthy adults. Naps can enhance alertness, mood, memory and creativity while offering other potential cognitive and cardiovascular benefits. However, napping may impair productivity over time and interfere with nighttime sleep patterns depending on nap timing, length and frequency. Understanding both the advantages and disadvantages of napping can help you decide whether integrating naps into your routine is likely to help or hinder based on your sleep habits, health status and lifestyle. Being thoughtful about when and how long you nap appears key to maximizing benefits while minimizing adverse outcomes.
References
1. Hayashi, M., Motoyoshi, N., & Hori, T. (2005). Recuperative power of a short daytime nap with or without stage 2 sleep. Sleep, 28(7), 829-836.
2. Morita, T., Ogawa, Y., & Uchimura, N. (2021). Effects of consecutive short naps on psychomotor vigilance and working memory performance. Nature and Science of Sleep, 13, 559.
3. Tietzel, A. J., & Lack, L. C. (2001). The short-term benefits of brief and long naps following nocturnal sleep restriction. Sleep, 24(3), 293-300.
4. Schabus, M., Hödlmoser, K., Gruber, G., Sauter, C., Anderer, P., Klösch, G., … & Zeitlhofer, J. (2008). Sleep spindle-related activity in the human EEG and its relation to general cognitive and learning abilities. European Journal of Neuroscience, 27(7), 1738-1746.
5. Mednick, S. C., Cai, D. J., Shuman, T., Anagnostaras, S., & Wixted, J. T. (2011). An opportunistic theory of cellular and systems consolidation. Trends in neurosciences, 34(10), 504-514.
6. Waterhouse, J., Atkinson, G., Edwards, B., & Reilly, T. (2007). The role of a short post-lunch nap in improving cognitive, motor, and sprint performance in participants with partial sleep deprivation. Journal of sports sciences, 25(14), 1557-1566.
7. Dhand, R., & Sohal, H. (2006). Good sleep, bad sleep! The role of daytime naps in healthy adults. Current opinion in pulmonary medicine, 12(6), 379-382.
8. Naska, A., Oikonomou, E., Trichopoulou, A., Psaltopoulou, T., & Trichopoulos, D. (2007). Siesta in healthy adults and coronary mortality in the general population. Archives of internal medicine, 167(3), 296-301.
9. Zaregarizi, M., Edwards, B., George, K., Harrison, Y., Jones, H., & Atkinson, G. (2007). Acute changes in cardiovascular function during the onset period of daytime sleep: comparison to lying awake and standing. Journal of Applied Physiology, 103(4), 1332-1338.
10. Tassi, P., & Muzet, A. (2000). Sleep inertia. Sleep medicine reviews, 4(4), 341-353.
11. Monk, T. H., Buysse, D. J., Carrier, J., Billy, B. D., & Rose, L. R. (2001). Effects of afternoon “siesta” naps on sleep, alertness, performance, and circadian rhythms in the elderly. Sleep, 24(6), 680-687.
12. Horne, J. A. (1988). Why we sleep: the functions of sleep in humans and other mammals. Oxford University Press.
13. Leng, Y., Wainwright, N. W., Cappuccio, F. P., Surtees, P. G., Hayat, S., Luben, R., … & Khaw, K. T. (2019). Daytime napping, sleep duration and increased 8-year risk of incident diabetes in a UK cohort. Sleep medicine, 57, 1-7.
