Hi there it's Matt Walker here and welcome back to a rather fascinating episode

that all starts with a conundrum. Should you gulp a coffee to boost your

flagging brain performance in the afternoon or should you take a nap? Well it's a

trick question at least in terms of this episode.

It's not one or the other, it's both.

Perhaps.

And we will come back to the caveat of perhaps right at the end of the episode.

But today we're going to speak about the rather ingenious suggestion of combining these what would otherwise seem like two arch nemesis together, which is sleep and caffeine.

And the technical term for this combination is, believe it or not, a caffeine nap.

In other words, you take your nap with an espresso chaser.

Uh-huh. I know, but a quick background 101 statement. In a previous episode called

the art of napping, I told you that naps of longer than around 20 to 30 minutes,

they lead to many generous brain benefits. However, they do come with the short-term cost of something that we call

sleep inertia. And sleep inertia, as you'll remember, is that somewhat unwelcome feeling of a slight sleep

hangover after the nap and it can take somewhere between 15 to 45

minutes to dissipate depending on how long you've napped.

In addition, in the episode, gosh it was many episodes ago on this show in the episode all about caffeine and I also went into somewhat great

depth about caffeine and sleep and alertness on the Tim Ferris show when I spoke with him.

We all know that caffeine will boost your

alertness levels once it starts to hit its peak concentrations in your

bloodstream or what we call your peak blood plasma concentrations.

But I also noted on both of those shows that caffeine can be harmful for your sleep.

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