As a Naptivist I spend a lot of time working to dismantle negative attitudes towards the humble nap and rest in general. In Western non-siesta cultures like ours, we tend to be deeply suspicious of anything that involves doing nothing for a while, so it can take a lot of proof before people are willing to try it. One of the best ways I have found to turn around even the most cynical of audiences is to present the scientific research.

10 minutes of sleep generates hours more alertness: numerous studies have demonstrated this. One study by Professor Leon Lack from Flinders University investigated the shortest nap possible to keeps workers perky. Out of a five, 10, 20 or 30-minute nap, he found that the 10-minute nap came up trumps. It caused an immediate increase in alertness to about the same degree as a half-hour nap, but without causing any ‘sleep inertia’ or grogginess. And the benefits lasted for the next two and a half hours – enough to get workers through the afternoon but without interfering with a good night’s sleep. To get 10 minutes of sleep, lie down for more like 20 minutes to allow time to drift off and set an alarm to wake you up.

The 10-minute nap is enough to reduce workplace accidents and errors: these are often errors that peak mid-afternoon and when shift workers are struggling to stay awake in the wee hours of the morning. Workplace accidents are costly. Napping is free.

In addition to its effect on alertness, the humble nap can have more profound payoffs. Dr Sara Mednick from the University of California found that napping might even make us smarter by improving memory. Her research has shown that:

• Short naps (up to 30 minutes) enhance muscle memory, helping us learn sequential movement sequences. That’s why some professional athletes nap as part of their training.

• 30 to 60 minute naps improve verbal memory – helping us to recall information we hear.

• Longer siesta-style naps of up to 90 minutes improve creative problem solving. So when you’re stuck on a problem the old saying to ‘sleep on it’ certainly has scientific merit.

Napping helps you learn by clearing out your mental ‘inbox’: this creates room to absorb new information. It may explain why some studies have found improved learning ability following a nap. Dr Matthew Walker, Professor of psychology at the University of California, Berkeley ran an experiment where 44 adults engaged in a learning session followed by immediate testing at midday, then again at 6pm. In between the two sessions half of the group napped for 1.5 hours, while the other half stayed awake. Learning ability in the No-Nap group deteriorated significantly, but the Nap group had better results at the 6pm test than at 12pm.

Caffeine versus Napping: when Dr Mednick compared the effects of caffeine versus napping on memory, she found that while napping and caffeine both improved alertness, caffeine made memory worse on two out of three tasks. A coffee might make you wired, but not very smart.

FAQs:

Why do I sometimes feel groggy after a nap? Grogginess, or ‘sleep inertia’ is caused by the deeper slow-wave-sleep that sets in at about the 30-minute mark, it takes a bit of time to lift. To avoid it keep naps to less than 30 minutes.

Does it matter what time of day I nap? Timing of the nap in relation to our body rhythms is important. The mid-afternoon nap has been shown to be more recuperative than a nap taken at other times of the day.

What if I don’t nap but simply rest?  You can still experience a significant improvement in mood.

What if I can’t nap! Some people report being unable to nap. This may be simply due to being ‘too wired’, in which case relaxation techniques can help. Or there may be other explanations that aren’t fully understood.