At some point, the nap got a bad reputation. The image of someone asleep in the middle of the day became shorthand for being… lazy. Which is a strange piece of cultural mythology when you consider that for most of human history, in most parts of the world, a midday rest was just what you did.
The idea that a productive day runs on a single unbroken stretch of wakefulness from alarm to bedtime is relatively new, and the science doesn't support it.
“Nature has not intended mankind to work from eight in the morning until midnight without that refreshment of blessed oblivion which, even if it only lasts twenty minutes, is sufficient to renew all the vital forces.”
— Winston Churchill
What happens to your brain when you nap?
Sleep moves through stages, and different stages do different things. The first 20 minutes or so involve light sleep (specifically stage 2) where the brain begins consolidating information and the body starts to recover. This is the sweet spot for a short nap: long enough to do something useful, short enough to avoid dipping into deeper sleep and waking up groggy.
Beyond 20 minutes you start moving into slow-wave sleep, which is harder to emerge from cleanly. A 90-minute nap takes you through a full cycle including REM, where emotional processing and creative thinking tend to happen.
What the research consistently shows is that a nap, almost regardless of length, restores alertness in a way that caffeine can't fully replicate. A NASA study found that a 26-minute nap improved pilot alertness by over 50%. Beyond immediate alertness, research links regular napping to better creative problem-solving and lower stress hormone levels, with one study finding that nappers were better at generating creative solutions than those who didn't rest.
None of this replaces a full night's sleep, but for days when you're running low, a nap is a more effective reset than another coffee.
What are the benefits of taking an afternoon nap?
- Increased alertness: A NASA study found a 26-minute nap improved pilot alertness by 54% and performance by 34% - more than caffeine alone manages.
- Creativity: Regular nappers perform better at generating creative solutions than people who don't rest mid-day.
- Stress: Napping is linked to lower cortisol and reduced stress hormone levels.
- Heart health: Frequent nappers have lower rates of heart disease.
- Brain health: Regular nappers show greater brain volume in older age, and one study found napping could slow brain ageing by three to five years.
Cultures where napping is normal: from Japan's inemuri to Spain's siesta
Japan has a concept called inemuri, which translates roughly as "sleeping while present." It's not frowned upon. Someone napping at their desk or on the train is often seen as a sign of dedication. The cultural assumption is the inverse of what we've inherited in the UK.
Spain's siesta is probably the most widely known example, though it's more layered than the tourist shorthand suggests. It originated in the hottest part of the Mediterranean day, when outdoor work was genuinely impossible and rest was the logical response to the climate. The word itself comes from the Latin "sexta hora", the sixth hour of the day, when Romans traditionally rested. This was people working with their biology rather than against it.
Parts of China and Latin America have similar traditions, rooted in the same logic: the body has a natural dip in the early afternoon, and a brief rest there is part of how the day was always designed to go.
Why you feel tired in the afternoon: the science behind the 2pm energy dip
Most people recognise the 2-3pm crash. The loss of focus, the impulse to reach for something. What's actually happening is a dip in core body temperature combined with a rise in adenosine, the chemical that accumulates the longer you're awake, both of which push the body toward sleep. This is a biological rhythm and humans share it with most other mammals.
The modern response is to push through, usually with stimulants. The historical response, across most of recorded human culture, was to rest briefly and get back to it.
The afternoon rest was never just about getting through the afternoon.
How long should a nap be?
The broad answer is: shorter than most people think.
A 10-20 minute nap restores alertness without leaving you groggy, because you haven't gone deep enough into slow-wave sleep to feel the drag of waking from it. This is why air traffic controllers in the US are directed to take 26 minute naps, and why the sleep pods at Google and Samsung are set to wake you after 20 minutes.
There's also the coffee nap, which sounds like a contradiction but works. Drinking a coffee immediately before sleeping for 20 minutes means you wake up just as the caffeine is kicking in, and studies have found it outperforms either coffee or a nap taken alone for sustained alertness.
The nap that tends to backfire is one in the 30-60 minute window, which drops you into slow-wave sleep and then cuts the cycle short. Waking from that stage tends to leave you more tired than before, which is probably where most bad nap experiences come from.
Successful people who nap: from Churchill to NASA
Churchill napped through the Second World War. In his own words, napping let him "press a day and a half's work into one." Einstein napped. Leonardo da Vinci reportedly slept in short bursts throughout the day rather than in one long stretch. Eleanor Roosevelt napped before speeches.
The pattern across high-output people throughout history is less "relentless wakefulness" and more "deliberate rest followed by focused work." Which is a different story to the one most of us absorbed about what productivity looks like.
Google, NASA, Samsung and the Huffington Post have all introduced nap spaces at their offices. The Huffington Post added nap rooms after Arianna Huffington realised how badly the culture had got rest wrong. That was 2007. The science has been piling up since.
Why napping feels lazy (and why that feeling is worth questioning)
The problem isn't the science. The problem is the cultural story we've inherited about what productivity looks like from the outside, and a nap doesn't look like it.
There's a specific performance around being busy: the badge of running on empty, the quiet pride in not stopping. Rest has been reframed as the absence of ambition rather than the thing that makes ambition sustainable. Most of us have absorbed this so thoroughly that lying down in the middle of the day, even alone, even when nobody can see, feels like cheating.
Which is worth sitting with. Because the majority of human cultures, across most of recorded history, thought it was just Tuesday afternoon.