Power naps: It's all about timing

Jan 08, 2020

Everyone knows sleep is important for wellbeing and quality of life. But there's evidence to suggest many people are becoming increasingly sleep deprived.

Insomnia is a common problem in Ireland. It affects around 1 in 5 people on a regular basis, and is particularly common in those who are older. In an international survey carried out by Aviva health insurance in 2017, 35% of Irish adults said they do not believe they are getting the right amount of sleep. The same survey ranked Ireland as the second most sleep-deprived country after the UK.

Benefits of power naps

One solution to reduce your sleep woes could be to take a power nap during the daytime. Scientists have shown that a power nap can be as refreshing as a good night's sleep. It could also improve your creativity, reduce your stress level, make you more alert, improve your memory and boost your performance and productivity at work. One study, which was presented at a European Society of Cardiology annual conference in London, also suggests napping may reduce your blood pressure.

But not everyone's a fan of power napping, and many complain it can make you feel groggy afterwards - which is hardly the result you may be going for. That groggy feeling is known in the sleep world as sleep inertia. It's the feeling of not being fully awake - indeed, it's thought to happen because part of your brain is still asleep.

A typical period of sleep inertia can last up to 30 minutes, though you may be affected for up to 4 hours. People who experience it - either when they are woken by their alarm clock first thing in the morning or after taking a nap - can have trouble doing even the simplest of things while they're affected. And to overcome it, they may rely on a strong cup of coffee (or 2) to get them going.

Sleep inertia and the sleep cycle

Sleep inertia is thought to be the result of being woken up while you're in part of the sleep cycle called REM (rapid eye movement) sleep. The entire sleep cycle lasts about 90 minutes, during which there are 5 stages. REM sleep is the last of these 5 stages; the first 4 stages make up NREM (non-rapid eye movement) sleep.

The REM stage is when you dream. Your brainwaves also speed up, your muscles relax, your breathing becomes more rapid and shallow and your heart rate increases. But if you're suddenly woken during the REM stage, your body may be producing high levels of a hormone called melatonin, which makes you feel sleepy.

Some scientists believe the way to combat sleep inertia when it comes to napping is to either wake after 90 minutes (that is, after an entire sleep cycle) or after 15 - 20 minutes.;

If you have the time, a 90-minute nap is considered ideal if you want to remember something you've just learned, since research suggests longer naps may help boost memory.

But if you simply want to feel less tired, try not to nap for longer than 20 minutes. That's because, apart from newborn babies who spend half their total sleep time in REM sleep, most of us spend a quarter of our sleep time in REM sleep. REM is the final stage of sleep, so the further along the sleep cycle you are when you wake, the harder it may be to feel alert.

How to nap effectively

If you're new to power naps, you may not find it easy to fall asleep quickly when it's not your regular bedtime. So here are a few tips to send you on your way:

Schedule your nap

If you nap at the same time every day, it could help train your body to fall asleep quickly and wake at the right time. The time of day for your nap could be important too. It's common to experience an energy dip after lunch, so aim to take your power nap in the middle of the day, between 1 - 3pm. If you nap any later, you may find it affects your ability to fall asleep at night.

Switch off your phone

It goes without saying that a constantly ringing phone won't help you nod off. If you don't want to be disturbed, put your phone on silent. Also place your phone out of reach, so you'll be less tempted to check your texts or emails when you should be relaxing.

Block out the light

The darker your environment, the more likely you'll fall asleep faster. If you can't find a dark enough room or corner, try wearing a sleep mask. 

Mask distracting noises

If you're taking a nap at work the normal sounds of office life may keep you awake. Turning on a fan can mask those noises. Or you could download a white noise app on your phone, as many people find they help them fall asleep in noisy environments.

Keep warm

Your body temperature naturally falls when you sleep, so make sure you have a blanket to keep you warm.

Fit it around your schedule

If you don't have time for a 20-minute nap, studies suggest shorter naps - even 5-minute ones - can also be effective.

Article reproduced with the kind permission of CABA, the organisation providing lifelong support to ICAEW members, ACA students and their close family around the world.