The results are in: napping is awesome. Although we may rebel against naps as children, most adults will attest to the fact that a quick doze during the day is all it takes to stay productive and alert. But according to sleep science, this notion is only half-true.
According to a recent study, the key to effective napping is trimming the time you’re actually asleep to precisely 10 minutes. For the study, researchers divided subjects into five groups based on the amount of time they were allowed to sleep without interruption: 5, 10, 20, and 30 minutes, as well as a control group that didn’t sleep at all. Once their naps had concluded, all subjects were tested on their productivity, cognition, and other factors measuring physical and mental alertness. The results of the study were:
- Subjects who slept for 5 minutes recorded similar results as the ‘no-nap’ control group.
- Subjects who slept for 10 minutes immediately improved in a wide range of areas, including “sleep latency, subjective sleepiness, fatigue, vigor, and cognitive performance”; furthermore, these subjects maintained these improvements for up to 155 minutes.
- Subjects who slept for 20 minutes began to exhibit improvements 35 minutes after the nap ended, and maintained these improvements for 125 minutes.
- Subjects who slept for 30 minutes immediately displayed a “period of impaired alertness and performance”, but eventually showed improvements that were maintained for up to 155 minutes.
The findings follow basic sleep science: after 20 minutes of napping, we fall into a pattern of intense restfulness known as ‘sleep inertia’. The longer we remain inert, the more difficult it is to function at full capacity once we’ve woken up. That’s why you’re more alert if a strange noise wakes you up after one hour of nighttime sleep, compared to the same noise waking you up after three or four hours of sleep. It’s also why you should keep your naps below the 10-minute mark.
When you choose to nap is just as important as the length of time you sleep. This determines your ‘chronotype’, or the time you would choose to sleep and be awake if your daily schedule was entirely up to you.
Let’s assume you are an average adult that requires roughly eight hours of sleep per night in order to function properly the following day. If you go to bed at 9 or 10 p.m. and rise for the day at 5 or 6 a.m., then you’ll start to naturally crave some naptime around 1 or 1:30 p.m. This window period is known as your ‘sleep gate’. If you rise later in the morning, your sleep gate will occur in the mid to late afternoon. Follow your chronotype, and you’ll be napping at the best time of day.
Lastly, your napping environment is crucial. Many workplaces today feature a ‘quiet area’ where people can get some shut-eye for a moment, and this will obviously be your best option for a napping spot. If this isn’t available at your office, then try to find a conference room or other area with comfy furniture that you’ll be able to claim for yourself. Dim the lights, draw the shades, and adjust the temperature to a moderate level. Of course, it goes without saying that napping against the wishes of your supervisor is highly discouraged.
In summation: a 10-minute nap during your natural ‘sleep gate’ in a quiet, comfortable setting is all it takes you get back on your feet after a rough night in dreamland.
