Hi there. It's Matt Walker here and welcome back to the podcast. Now how can you

really argue with the great Roman poets and one such splendid Roman poetic genius was

ovid and he once said there is more refreshment and stimulation in a nap, even of the briefest than all the alcohol ever distilled.

Clearly, Ovid should have been a sleep research as a brilliant insight but are naps a good thing or are

naps a bad thing are they even a natural thing and furthermore if do nap, when should you nap and for how long should you nap.

Today's episode is all about napping.

Let's start with the question of how humans were designed to sleep.

Most people throughout developed nations aim to get their recommended 7 to 9 hours of sleep

in one long stretch at night. And the technical term for this is

monophasmic sleep in other words a single bout of sleep at night. However we may not have been programmed to sleep in this way. And as we

discussed in our episode on circadian rhythms, we become more alert and awake into the morning, yet in the middle of the afternoon

we can experience this beautiful biologically pre-programmed drop in our alertness as if we should be asleep for a short period of time during the afternoon.

And I'm sure you've had that experience. I've had it plenty of times. That sort of drop in alertness,

where you just start to feel sleepy in the afternoon.

And you can even see this in other people,

I think I've mentioned,

as their heads begin sort of bobbing up and down during afternoon meetings it's a

dead giveaway of what's happening. Now you may think that this drop in afternoon alertness

happens because of perhaps a big lunch but it's not it's

down to your biology if I place electrodes on your head I can measure this pre-program drop in your brain's alertness every afternoon, no matter whether

you've had a big lunch or a small lunch or no lunch at all.

And for most of us, it happens somewhere between the 1 to 4 PM mark. What this suggests is that we may have been designed to sleep in a biphasic pattern, meaning one long about of sleep at night and then a short afternoon nap during the day,

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