Ah, a nap. How good we feel after we take one (or not). I’m not a napper, although I wish I could be. When I was young I always took a long nap on Sunday afternoons, and I always woke up feeling groggy. These days I take short naps occasionally (usually under 20 minutes). When I manage to take one I wake up refreshed and able to continue with my day. It seems that I’ve inadvertently stumbled on something that researchers have been examining for quite some time.
Why Nap?
There are actually a number of proven benefits to napping.
- Napping improves mood – Perhaps it’s just the increased sleep, perhaps it’s not being cranky because you are tired. Whatever the case, napping consistently has been shown to improve mood.
- Napping reduces fatigue – Well, that seems obvious. Any sleep should help improve fatigue, but regular napping decreases not only the fatigue of a bad night’s sleep but the fatigue that we feel as we hit that mid-afternoon energy slump.
- Napping improves attention – Struggling to pay attention in those afternoon meetings? Perhaps heading to your car for a 15-minute nap before the meeting will help. Those who nap show a greater ability to pay attention than those who don’t.
- Napping improves performance – A 2005 study by Hayashi et al. showed that performance and alertness dip through lunchtime when no nap is taken, but a short nap improves performance on logic, math, and reasoning tasks.
- Napping improves reaction time – This may be the most important reason for those who are sleep deprived to nap. Whether you are driving or your work requires a quick reaction time, a nap can help you.
- Napping improves memory – Napping improves both declarative memory (the ability to recall what you know) and procedural memory (the ability to recall how to do stuff).
- Napping may reduce your need for sleep – According to Timothy Ferriss, the author of The 4-Hour Body, for every nap you take during the day your need for sleep reduces by two hours.
Of course, most of us just grab a coffee in the afternoon to get us through the slump. So how does a nap compare with coffee? The benefits of a nap are more reliable and last longer than caffeine. Naps don’t leave you with the jitters or a post-caffeine crash. They just work. Following your nap with caffeine will give you the greatest benefit.
Timing matters. The benefits of your nap are affected by timing in two ways: when you take the nap and how long you nap.
- Timing of the nap – If you generally sleep well at night, you’ll get the most benefit from a nap taken sometime between 2 and 5 p.m. This is typically when your circadian rhythm dips, leaving you feeling tired. Naps during this timeframe show a greater improvement in performance than naps taken before the post-lunch dip. Of course, if you sleep later, then your nap should come later too. If you don’t generally sleep well at night and are sleep deprived, you’ll likely benefit the most from an earlier nap.
- Nap duration – How long you nap matters, but how long is too long and how long is too short? Five minutes is too short, but short naps of 10–20 minutes show the greatest benefit. Naps longer than 20 minutes are still beneficial, but they come at a price. You wake up groggy, and it takes a while to clear your head, thus delaying the benefits. The longer the nap the longer the delay between the nap and when the benefits are seen. Naps longer than an hour show diminishing returns; basically you get the same benefit from a 2-hour nap that you’ll get from a 1-hour nap.
Additionally, researchers have found that those who nap daily get more restorative benefit from their naps than those who just nap occasionally.
So take a little time each day—but not a lot—and schedule a nap. You’ll be glad you did after you reap the benefits of improved attention, alertness, performance, reaction time, and a better mood. Go ahead, take a nap. It’s good for you!
Source: Milner CE, Cote KA (2009). Benefits of napping in healthy adults: impact of nap length, time of day, age, and experience with napping. Journal of Sleep Research, 18(2):272–281.