"Time to get ready for bed!" someone calls from the
other room. Oh, no! You're really into the great book
you're reading or that computer game that you're
winning.
"Why do I have to go to bed?" you ask. "Sleep is
boring, and I'm not even tired!"
But sleep is more important than you may think. Maybe you can
think of a time when you didn't get enough sleep. That heavy,
groggy feeling is awful and, when you feel that way, you're not
at your best. So if you're not too tired, let's talk about
sleep.
Why You Need Sleep
The average kid has a busy day. There's school, taking care
of your pets, running around with friends, going to sports practice
or other activities, and doing your homework. Phew! It's tiring
just writing it all down. By the end of the day, your body needs a
break. Sleep allows your body to rest for the next day.
Everything that's alive needs sleep to survive. Even your
dog or cat curls up for naps. Animals sleep for the same reason you
do - to give your body a tiny vacation.
Not only is sleep necessary for your body, it's important
for your
brain
, too. Though no one is exactly sure what work the brain does when
you're asleep, some scientists think that the brain sorts
through and stores information, replaces chemicals, and solves
problems while you snooze.
Most kids between 5 and 12 get about 9.5 hours a night, but
experts agree that most need 10 or 11 hours each night. Sleep is an
individual thing and some kids need more than others.
When your body doesn't have enough hours to rest, you may
feel tired or cranky, or you may be unable to think clearly. You
might have a hard time following directions, or you might have an
argument
with a friend over something really stupid. A school assignment
that's normally easy may feel impossible, or you may feel
clumsy playing your favorite sport or instrument.
One more reason to get enough sleep: If you don't, you may
not grow as well. That's right, researchers believe too little
sleep can affect growth and your
immune system
- which keeps you from getting sick.
The Stages of Sleep
As you're drifting off to sleep, it doesn't seem like
much is happening . . . the room is getting fuzzy and your eyelids
feel heavier and heavier. But what happens next? A lot!
Your brain swings into action, telling your body
how
to sleep. As you slowly fall asleep, you begin to enter the five
different stages of sleep:
Stage 1
In this stage, your brain gives the signal to your muscles to
relax. It also tells your heart to beat a little slower, and your
body temperature drops a bit.
Stage 2
After a little while, you enter stage 2, which is a light sleep.
You can still be woken up easily during this stage. For example, if
your sister pokes you or you hear a car horn outside, you'll
probably wake up.
Stage 3
When you're in this stage, you're in a deeper sleep,
also called slow-wave sleep. Your brain sends a message to your
blood pressure to get lower. Your body isn't sensitive to the
temperature of the air around you, which means that you won't
notice if it's a little hot or cold in your room. It's much
harder to be awakened when you're in this stage, but some
people may sleepwalk or talk in their sleep at this point.
Stage 4
This is the deepest sleep yet and is also considered slow-wave
sleep. It's very hard to wake up from this stage of sleep, and
if you do wake up, you're sure to be out of it and confused for
at least a few minutes. Like they do in stage 3, some people may
sleepwalk or talk in their sleep when going from stage 4 to a
lighter stage of sleep.
REM
This stands for Rapid Eye Movement. Even though the muscles in
the rest of your body are totally relaxed, your eyes move back and
forth very quickly beneath your eyelids. The REM stage is when your
heart beats faster and your breathing is less regular. This is also
the stage when people dream!
While you're asleep, you repeat stages 2, 3, 4, and REM
about every 90 minutes until you wake up in the morning. For most
kids, that's about four or five times a night. Who said sleep
was boring?
Dream a Little Dream
You're walking down the street and you pass a monkey in a
green hat eating a donut. Suddenly you're in school - but why
does your teacher have such big teeth? And how come you're
wearing polka-dot pants?
No, this isn't a scene from a scary movie - it's a
dream!
People dream during REM sleep, the period that follows the
deepest stage of sleep. Everybody has dreams, although some people
have a tough time remembering them. When you wake up can affect
whether you can remember your dreams. If you wake up during REM
sleep, you might remember everything about your dream. If you wake
up during another stage of sleep, you might not remember a
thing.
No one knows for sure why people dream. Some scientists think
that dreams are your brain's way of making sense of what
happened during the day. Others think that dreams allow your brain
to sort through the events of the day, storing the important stuff
and getting rid of the junk. Some scientists say that dreams are a
clue to what you're worried about or thinking about.
How to Catch Your ZZZs
For most kids, sleeping comes pretty naturally. Here are some
tips to help you catch all the ZZZs you need:
- Try to go to bed at the same time every night; this helps
your body get into a routine.
- Follow a bedtime routine that is calming, such as taking a
warm bath or reading.
- Limit foods and drinks that contain
caffeine
. These include some sodas and other drinks, like ice tea.
- Don't have a TV in your room. Research shows that kids
who have one in their rooms sleep less. If you have a TV, turn it
off when it's time to sleep.
- Don't watch scary TV shows or movies close to bedtime
because these can sometimes make it hard to fall asleep.
- Don't
exercise
just before going to bed. Do exercise earlier in the day - it
helps a person sleep better.
- Use your bed just for sleeping - not doing homework, reading,
playing games, or talking on the phone. That way, you'll
train your body to associate your bed with sleep.
If you have a hard time falling asleep for more than one or two
nights or have worries that are keeping you from sleeping, tell
your mom or dad. They can help you solve your sleep problems. In
fact, just talking about it with them could help you relax just
enough (yawn) that you'll be ready to sleep.
Zzzzzzzzzzzzzzz.
Updated and reviewed by:
Mary L. Gavin, MD
Date reviewed: August 2007
Originally reviewed by:
Michael Goodman, MD
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
© 1995-2009 The Nemours Foundation/KidsHealth. All rights reserved.