A heartbeat has two parts. They are sometimes called lubb and dubb because those are the sounds that a doctor hears. A lubb happens when the upper chambers of the heart contract to squeeze the blood downward into the ventricles. A dubb happens when the lower chambers contract.

Heart Diagram from Pediheart

Every time the lower chambers of the heart contract, the blood in the left ventricle rushes upward into the aorta. It quickly speeds away from the heart causing the aorta to expand as it passes. As the blood races along, some of it pushes into the first artery that branches off from the aorta. Some of the blood enters the next artery.

The blood from each contraction of the heart produces a bulge in the artery. We call that bulge a pulse. One pulse equals one heartbeat.

The pulse can be felt anywhere an artery passes close to the skin. Common places to feel a pulse include the wrist, neck, temple, behind the knees, and on top of the foot.

To feel the pulse in the wrist, place your index and middle finger over the underside of your opposite wrist, below the base of the thumb. Press firmly with flat fingers until you feel the pulse.

To feel the pulse on the neck, place your index and middle finger just to the side of your Adam's apple, in the soft hollow area. Press firmly until a pulse is felt. Once you find your pulse, count the beats for 1 full minute.

You can get an approximate pulse by counting for 30 seconds and multiplying by 2, or by counting for 15 seconds and multiplying by 4. The easiest approximation comes from counting for 6 seconds then adding a zero.

The bad thing about approximations is that they become less and less accurate as you count for shorter and shorter times. But in the test you are doing, the pulse may be changing rapidly. When the pulse is changing rapidly, the shortest count may be the most accurate.

If a resting heart rate is what you want, you must have been resting for at least 10 minutes. The exercise heart rate is obtained while you are exercising, or for the 6 seconds immediately after you stop.

Why do doctors take your pulse?

Your pulse can give your doctor important information about your health. If your heart rate is normal, that doesn't say very much, but if it is not normal you may have a problem.

A fast resting pulse can mean that you are dehydrated or have an infection. A slow resting pulse can mean that your heart is very strong and healthy. How quickly your heart rate returns to normal after exercise gives information about your fitness.