Listen to the Lub-Dub
When you go for a checkup, your doctor uses a stethoscope
to listen carefully to your heart. A healthy heart makes a lub-dub
sound with each beat. This sound comes from the valves shutting
on the blood inside the heart.
The first sound (the lub) happens when the mitral and tricuspid
valves close. The next sound (the dub) happens when the aortic
and pulmonary valves close after the blood has been squeezed out
of the heart. Next time you go to the doctor, ask if you can listen
to the lub-dub, too.
Pretty Cool — It's My Pulse!
Even though your heart is inside you, there is a cool way to
know it's working from the outside. It's your pulse. You can find
your pulse by lightly pressing on the skin anywhere there's a large
artery running just beneath your skin. Two good places to find
it are on the side of your neck and the inside of your wrist, just
below the thumb.
You'll know that you've found your pulse when you can feel a
small beat under your skin. Each beat is caused by the contraction
(squeezing) of your heart. If you want to find out what your heart
rate is, use a watch with a second hand and count how many beats
you feel in 1 minute. When you are resting, you will probably feel
between 70 and 100 beats per minute.
When you run around a lot, your body needs a lot more
oxygen-filled blood. Your heart pumps faster to supply the oxygen-
filled blood that your body needs. You may even feel your heart
pounding in your chest. Try running in place or jumping rope for a
few minutes and taking your pulse again — now how many beats do
you count in 1 minute?
Keep Your Heart Happy
Most kids are born with a healthy heart and it's important to
keep yours in good shape. Here are some things that you can do
to help keep your heart happy:
Remember that your heart is a muscle. If you want it to be
strong, you need to exercise it. How do you do it? By being active
in a way that gets you huffing and puffing, like jumping rope,
dancing, or playing basketball. Try to be active every day for at
least 30 minutes! An hour would be even better for your heart!
Eat a variety of healthy foods and avoid foods high in unhealthy
fats, such as saturated fats and trans fats (reading food labels can
help you figure out if your favorite snacks contain these unhealthy
ingredients).
Try to eat at least five servings of fruits and vegetables
each day.
Avoid sugary soft drinks and fruit drinks.
Don't smoke. It can damage the heart and blood vessels.
Your heart deserves to be loved for all the work it does. It
started pumping blood before you were born and will continue
pumping throughout your whole life.
kidhealth.org
Of f icialKidsMag.com • FEBRUARY 2020 • 13
