Naps vs. caffeine vs. more night sleep

What's the best way to beat afternoon sleepiness? (drumroll) Go to sleep! Loughborough University researchers compared three methods to beat normal daytime sleepiness: more sleep at night, an afternoon nap earlier that day, or caffeine. During the study, volunteers who either napped, slept late, or took a caffeine pill, were put in a quiet room and invited to close their eyes. The researchers then compared how long it took them to fall asleep. From Science News:
The researchers compared sleeping in for 90 minutes each morning to taking a 20-minute nap at 2:30 p.m. or taking 150 milligrams of caffeine (equivalent to about two cups of coffee) at 2:00 p.m...

When the volunteers did nothing, they fell asleep within nine minutes on average when tested at 3:30 in the afternoon. Sleeping late kept people awake only a minute longer on average than did doing nothing. Caffeine worked better, keeping people awake for about 12 minutes longer on average.

But nothing beat a nap. After a 20-minute nap, people nearly doubled the amount of time it took to fall asleep when tested later in the afternoon, indicating that they were no longer sleepy. None of the measures impaired people’s ability to fall asleep at night.


  1. I’ve read that a combination of two methods works the best: drink a cup of coffee and then immediately nap. The coffee kicks in at nap’s end, bringing you awake with a snap.

  2. Huh? Not falling asleep quickly = not being sleepy?

    Nap makes lots of people GROGGY.

    try exercise instead. Oh, an *active*response? In America?

  3. Wait a second wait a second….

    Taking a nap doubled the amount of time needed to fall asleep. I assume “doubled compared with caffeine”, although it doesn’t say. So it took them 24 minutes to fall asleep. And they had slept for 20 minutes before hand…

    Net total awake time compared with not napping: 4 minutes?!?

    Ok, ok, I get that the time taken to fall asleep is just supposed to be a measure of how tired you are, but it’s not a very good one. Are they awake and productive, or can they just not fall asleep and are tired and grumpy? And if they are productive, is their productivity worth the twenty minutes they spent sleeping?

  4. Wow, people can fall asleep at three in the afternoon? I have enough problems doing it at three in the morning.

  5. naps however have the inherent disadvantage, overlooked by this study, of creating wildly lucid dreams and blurring the line between reality and imagination. maybe people can stay awake for longer just because their head is too tangled with confusion to think about falling asleep~

    naps? can’t do ’em!

  6. I agree with the excercise comment. 20 pushups and you can just forget everything else. What a waste of a study.

  7. Hooray for siesta! This does seem to be an excellent way of coming awake again when dog tired. (I think it’s essentially rebooting your circadian rhythm.)

  8. @thievedrelic (#5),

    You said:
    “naps however have the inherent disadvantage, overlooked by this study, of creating wildly lucid dreams and blurring the line between reality and imagination.”

    For me, those aren’t bugs but rather features!

  9. I’m kind of impressed that everyone fell asleep when left in a quiet room with their eyes closed. I wouldn’t have thought it would be that easy to provoke sleep if someone wasn’t sleep-deprived.

  10. Very simple way to avoid afternoon fatigue is to not eat carbohydrates with your lunch (and why not breakfast and dinner as well ;-)).

    Biggest improvement for general alertness comes from correct diet. IMHO.

  11. All of the above. Sleep when tired. Drink when thirsty. If it’s 3:00 AM and you’re wide awake, raise the snark quotient of your favorite blog’s comments.

  12. Here’s my tried-and-true technique for all of you to try.

    Drink a decent quotient of caffeine during the day as to feel it, yet not become acclimated to it.Don’t go crazy; consider this a cup or two of coffee or two Dews. You get the idea.
    Your last cup or can of the stuff shouldn’t be within say, 3 or 4 hours of bedtime.

    An hour before bed, drink a larger MG dosage than your normal amount of caffeine. If you’re used to normal drip coffee, down a shot of espresso.
    The shock to the system will bring you the ‘caffeine crash’ and help you sleep.

    Alternatively, try something that’s foolproof. If you find yourself only able to sleep say 3-5 hours before you have to get up, take a multivitamin before you sleep. You’ll wake up 100% refreshed.

  13. Problem is, every time I go to sleep it’s like at least an hour or two. None of these 20-minute naps. They just make me groggy and mad that I didn’t get to sleep 2 hours.

  14. I think the fact that all the participants were suffering from caffeine withdrawal might bias the results.

  15. Looking through the comments I see a lot of people complaining about naps making them groggy. Well, I happen to have, uh, studied sleeping patterns extensively in college (I majored in English), and then researched my findings.

    First, I found that a 10-15 minute nap in the afternoon refreshes me and makes me more alert. BUT, 20-30 minutes, and I’m groggy for the rest of the day unless I sleep a solid 3 hours. This struck me as odd, so I did some digging. Here’s what I found:

    When you first go to sleep, you slip into a light sleep. From there, you will eventually go into a deep sleep for about an hour (this varies considerably, but it’s about a 90 minute cycle, all told), and then come back out of it to light sleep. You cycle like this throughout the night, usually going through 3-5 cycles per night.

    Thus, if you can take a short nap and wake up before you slide into deep sleep, you’ve essentially refreshed the body without putting the brain into night mode which makes you groggy.

    On a similar note, I find it easier to get up at 6 am than at 7:20- I strongly suspect this is because at 6 I’m in a light sleep cycle, and at 7:20 I’m in deep sleep.

  16. Interesting that they found caffeine in the afternoon didn’t impair people’s ability to fall asleep at night.

    I know if I have even one cup of coffee at 2:00 or 3:00 PM, I’m twitching and fidgeting when it comes time for bed. A cup of tea not especially strong tea and a piece of fruit is enough to keep me alert through the afternoon doldrums on all but the worst days.

  17. Never mind naps making you groggy. How do you prevent the horrible headache that only a full night’s sleep can cure?

  18. My take on naps: Find the right amount of time. For me half an hour can be too long and I’m groggy. Even resting your eyes for 10 or 15 minutes gets me refreshed. Even if I’m awake the whole time.

  19. @Geonz:

    try exercise instead. Oh, an *active*response? In America?

    You do realize that Loughborough University is in the UK, right?

  20. I found that mid-afternoon sleepiness was an effect of blood-sugar crashing in my case. When I was on a diet that required me to eat five or six small meals, no more than two or three hours apart, those post-lunch groggies went away. (Also: These were moderate-carb meals. Whole-grain pita instead of big fluffy roll, that sort of thing.)

    When I stopped doing that, and went back to my bad old habits, the groggies came back.

  21. For me a twenty minute nap is worse than no nap at all. I need like an hour for it to help. I’d rather just get nine hours at night, but alas…

  22. >Interesting that they found caffeine in the afternoon didn’t impair people’s ability to fall asleep at night.
    It’s ridiculously easy to build up a tolerance to caffeine. Drinking two or three cups of coffee a day, it only takes about two weeks to build up near-complete tolerance to the stuff.

    Once you’ve hit that point, all caffeine does is not make you feel like shit once you’ve had your maintenance dose for the day.

  23. I suffer from chronic afternoon tiredness – borderline narcolepsy. I’ve struggled to find a solution but here’s what helps:
    Less carbs at lunch definitely helps.
    Slow release breakfast (oats generally) helps.
    More sleep! Not easy for me, I am a rage against the dying light night owl.
    Power naps – less than described in the article <5 mins does it for me, just enough to flip into a lucid dream. I've read before you should sit holding a spoon loosely in one hand. When you drop off the spoon will hit the floor and wake you. I'm good to go after just a moments 'sleep'. This isn't recommended on the motorway however (where unfortunately 10mins driving is enough to induce the nods in me.
    No interruptions from the kids is a massive bonus. This was more of a problem when they were tiddlers.

    Despite all my precautions and techniques I still suffer. I know have sleep apnoea which scares the hell out of anyone who's slept in the same room as me. As yet I haven't tried treatment for this. I'm going to look into it right now.

  24. A bit of that post got eaten by my dumb use of a bracket.
    As it should have been:
    Power naps – less than described in the article less than 5 mins does it for me, just enough to flip into a lucid dream. I’ve read before you should sit holding a spoon loosely in one hand. When you drop off the spoon will hit the floor and wake you. I’m good to go after just a moments ‘sleep’. This isn’t recommended on the motorway however (where unfortunately 10mins driving is enough to induce the nods in me.

  25. Firstly, I don’t sleep well, I usually get to sleep okay but then wake up very easily or too early and spend the rest of the day feeling tired.
    If I have a nap (say 30 minutes) I feel refreshed again but then have trouble getting to sleep at my normal time – so instead I struggle through the day feeling tired. Which is a bunch of arse, really.

  26. Naps rock. I take a nap every work day, during the 1/2 hour I have for lunch, and it’s wonderful.

  27. I was a student at Loughborough, and took part in one of the sleep research unit’s experiments. The role-playing society were, after all, quite willing to be paid to stay up all weekend. Sadly, the sleep research unit is fond of publicity, and doesn’t design its experiments as carefully as one might like. Treat their results with considerable caution.

  28. The days I don’t eat lunch (because I’m not hungry) I don’t get tired.

    The days I play basketball at lunch I get EXTREMELY tired.

    I end up driving home and not remembering half the trip because I’m just this side of nodding off.

    You get the afternoon sleepies because you sit at computer for 6 hours, your brain probably just thinks you’re not doing anything and shuts off.

    I’d love to be able to take a nap at work, anyone have the Costanza desk for sale?

  29. i always take a nap in afternoon.i feel like my energy is fully recharged. :D It really helps me to stay awake in the night for doing my lot of assingnment. taking a nap in the afternoon is more much better than drinking a cup of coffee in night, to help us staying awake in the night, it’s healthier i think :)

Comments are closed.