Dr. Matt Walker

They are designed to adaptively help us survive.

But you can't go to the extremes.

That's maladaptive rather than adaptive.

But that's where you go when you are sleep deprived.

It's this loose hinge and you become very, very erratically and extremely reactive from a neural perspective.

I would say just to keep it high level and brief, the single best way –

cheapest non-pharmacological way that you can enhance your REM sleep is to just sleep an extra 15 or 20 minutes later into the morning don't try to put if i tell you this is about by the way this is about the the quantity that your sleep opportunity

Don't try to add that 30 minutes or 20 minutes if your goal is to increase REM sleep at the start of the night at the front end.

Instead, take that desire that I've offered you of adding just 20 minutes or 25 minutes of extra sleep now to the...

last part of your night, wake up that sort of much later, 20, 25 minutes later, that's the REM sleep rich phase.

So if people go back and listen to episode one, we'll describe to you exactly how the different stages of sleep unfold across the night.

And they're not evenly distributed.

It's not as though you get just as much REM sleep as well as deep non-REM sleep in the first half of the night as you do in the second.

You get most of your deep sleep in the first half, and you get most of your REM sleep in the second half, and particularly in the last quarter of the night.

And this leads us to understand that the later into the morning hours that we go, the greater the hunger preference and the taste desire that is of your brain to start sampling from the finger buffet of all of those different stages, this thing called REM sleep.

And the later that you sleep into the morning, the more of that REM sleep that you will have.

And many people will have experienced this at the weekend, where they have this pattern that we don't recommend based on the QQRT.

QQR, regularity, go to bed at the same time, wake up at the same time.

What we see often in society is something that we call social jet lag, where you're short sleeping during the week, and then at the weekend...

you're out with friends or you're out sort of on the town, you go to bed late and you wake up late,