- Hi, I'm Dr. Tracey Marks, a psychiatrist
and I make mental health education
and self improvement videos.
Today I'm gonna help you understand
how naps affect your sleep pattern
and when's the best time to get one.
Short 20 to 30 minute naps can give you a boost
in mental energy and cognitive abilities
as long as they are in the early afternoon
and not too close to bed time.
These are what we call power naps.
Here's why they should be short.
When you sleep you go through four stages,
the light stages of sleep one and two,
a deep stage and then REM sleep.
This is one cycle and it's called your sleep architecture.
It takes about 90 minutes to go through one cycle.
How long you spend in each stage
varies from person to person
but on average it can take about 20 to 30 minutes
to go from stage one down to stage three
where you have deep sleep.
So, if you wake up from the light stage of sleep
you can more quickly spring back into action
but if you wake up from a deeper stage of sleep
you could feel groggy and tired like you need more sleep.
So you may say if sleeping 40 minutes makes you feel worse
then just try to push it to two hours
then you get more sleep
and you can still wake up feeling rested.
Not necessarily, sleeping too long depletes
your homeostatic sleep drive
and here's what that is.
During the day when you're awake and thinking
your brain creates energy biproducts.
These biproducts build up over the course of the day
until it reaches a tipping point
to push you over into sleep.
This is called your sleep drive.
Some people will call it a sleep debt
so at your usual bedtime you have a number of factors
that help you fall asleep,
your body clock telling you that it's bedtime,
your body temperature and your sleep drive.
If you think of the drive as money in a bank,
when you take a nap you spend money from the bank.
With a long nap you may fall below the threshold
of what you need to be driven to fall asleep.
So this is why when you sleep makes a big difference
with how easy or how hard it is to fall asleep
at your usual bedtime.
If you take a long nap early in the day
you still have several hours
to build back up your sleep drive
but if it's too close to bedtime
you may need to be awake for longer to get sleepy again.
Most people have experienced this
and it makes sense but this is the explanation for it.
Sleeping takes away from your sleep drive.
So back to the power nap.
The best time to take it is early in the afternoon
around two to 3 p.m.
This gives you a chance to recover your sleep drive
and it also helps you with the natural dip in alertness
that you may feel in the afternoon.
The usual pattern with your body clock
is that you have a dip in energy and alertness
in the early afternoon.
We associate this with having a heavy lunch
and that may make it worse
but even aside from what you eat
you can still feel slowed down
or even a little drowsy in the early afternoon.
You can address this by overriding the triggered sleep
by taking a walk or doing some other form
of brief activity or exercise
or you could take a power nap.
You may need to set an alarm though
to keep yourself from sleeping too long.
If you take a 30 minute nap in the evening
it may not be enough to keep you from going to bed
at your regular time
but you may alter your sleep architecture
for the rest of the night.
I mentioned that you go through these different stages
in 90 minute cycles and have about four to six cycles
over the course of a night.
The normal sleep architecture
is to spend more time in deep sleep
in the first couple of cycles
then as the night progresses
you spend more time in the lighter stages
in REM also known as dream sleep.
So what this looks like is you spend the first half
of your night sleeping deeper
and the second half of your night sleeping lighter
and getting more and more ready to wake up.
So if you nap in the evening
even if you're still able to go back to sleep
you can change this normal sleep pattern
in a way that results in less deep sleep
or deep sleep that extends too long
into your allotted sleep time
then you have a hard time waking up.
So the moral of this story here
is that napping can be thought of
as plugging your brain in for a quick recharge
in the middle of the day
when you have a natural dip in your energy
and mental functioning.
If you decide to use naps to give yourself
an afternoon boost just make sure
to limit them to 20 to 30 minutes
and early in the afternoon.
Thanks for watching, see you next time.