Do power naps work? The science behind Boris Johnson’s reported Churchillian technique

Margaret Thatcher famously lived on just four hours of sleep a night during her prime ministership. President Donald Trump was also known to be catching between three and four hours a night when he was a New York businessman (the White House probably didn’t leave much room for more). Even Barack Obama, who by comparison is well rested, sits at the lower end of the NHS-recommended bracket at just six hours of sleep.

In recent years, as society moves at breakneck speed, technology interrupts our sleep cycles, and everyone is looking to best optimise their time awake (see the popular, “you have as many hours in the day as Beyoncé” memes), we have heard more about the routines of the rich and famous. In particular about their sleep schedules. For example, actor Mark Wahlberg left everyone scratching their heads when he revealed he wakes up at 2am to ensure a 3.15am breakfast and cryogenic chamber session.

This week, reports suggested that PM Boris Johnson was supplementing his sleep with a half-hour daytime kip. Although No. 10 has rebutted the claims, saying his schedule is too “jam packed” to do so, he wouldn’t be the first. Winston Churchill was known to hit the hay for between four and five hours a night and catch up with a 90-minute nap during the day.  

People have written about this style of fragmented sleep for centuries - Homer’s Odyssey even mentions sleeping in two distinct chunks rather than one overnight stint. Siestas are still common in other parts of the world, and a notable part of Spanish culture, although less prevalent than it once was. In modern Silicon Valley businesses, they choose to lean in to this, with the Google campus providing napping beds known as EnergyPods. The Ben & Jerry HQ has reportedly had nap rooms for over ten years.  But is napping actually a helpful tool to manage tiredness or is it better to leave the shut eye till after dark? 

The NHS says most adults need between six to nine hours of monophasic sleep - a single block of rest - every night. It doesn’t offer specific advice on napping other than to warn people from doing so if they are insomniacs, referencing advice from the Royal College of Psychiatrists which says you should avoid daytime sleep if you’re struggling to sleep overnight. 

The Sleep Foundation agrees that “napping isn’t for everyone”. It says: "In fact, some people find napping counterproductive. Although reducing sleep pressure can combat fatigue, it can also interfere with your ability to fall asleep.” But what about for those who have no trouble sleeping but enjoy a daytime nap? Are they purely a beneficial top up? 

Some studies have shown that naps can have a detrimental impact on your health, particularly on your cardiovascular system if you take longer naps, and even that there is a gender disparity between napping benefits (with men said to be getting an IQ boost in shorter sleep cycles, that women only get with deep sleep). But there are also well-documented advantages to napping too. 

Research by NASA looking at how to reduce the impact of employee fatigue found improvements in performance of about 34 per cent and alertness by 54 per cent following a power nap. A study by the University of California found that an hour’s nap could boost and restore your brain power. And a study from Harvard Medical school found post-napping, participants showed significant improvement on three of the four tests in the study's cognitive-assessment battery. The Sleep Foundation also says napping can improve learning, aid memory formation and help to regulate emotions. 

Professor Alice Gregory, author of Nodding Off, at Goldsmiths University of London, tells The Independent that napping preference can depend on the person: "Many people are sleep deprived and some people find napping very helpful. A nap can potentially increase alertness and mental well-being and support the immune system. 

“However, not everyone finds napping a positive experience and those who are experiencing insomnia are typically advised not to nap during the day, as a daytime snooze can make it more difficult to nod off at night.”

A 2016 clinical review, published in Sleep Medicine Reviews, examined how napping could be a powerful tool in addressing the well-documented sleep debt in our modern world.  It concluded that napping could be used as a countermeasure to the increased stress on our bodies, and that a 20-30 minute shut eye around midday did improve mood and mental states. But the nap did have to remain under 30 minutes long to be useful.

Dr Guy Meadows of The Sleep School, says although “there is no substitute to a good night's night”, “humans are biologically designed to sleep both at night and after midday and so it makes sense to reap the benefits of a short nap, after lunch”. He adds that even if you sleep well you might consider a nap “to boost your energy, alertness, mental performance and mood in the afternoon”. 

So if you’re thinking about starting, what are you looking to achieve? NHS advice to employees says: “For many people a short, 15 to 20-minute nap can help to reduce the impact of fatigue on their ability to function, especially at night. Power naps are enough to give a ‘boost’ of sleep that can leave you feeling more alert and less sluggish when you wake.” It says you can learn to power nap.

Professor Gregory says for the ultimate nap, keep it short and don’t rush to wake up: “It is often recommended that we should keep naps short (20 minutes for example) – to avoid experiencing sleep inertia (a groggy state) upon waking. However, even short naps can sometimes result in sleep inertia – so always give yourself time to properly wake up from sleep. It’s also advisable not to nap close to bedtime.”

Dr Guy adds that you should try between midday and 3pm. “Aim to set an intention to simply rest, rather than to sleep. The latter can create undue pressure, pushing sleep away. ”

As the coronavirus pandemic continues and millions of Britons work from home, perhaps 2021 is the perfect time to try out a daytime nap away from the glare of your employer (and near your own bed). But be warned, it isn’t a guaranteed winner for everyone, leaving some feeling worse than when they started. Now, if only we could hit snooze until the end of lockdown.