Heart and Heart Rate

It's approximately the size of your fist

It weighs less than a pound (lb) (less than a block of butter!)

It has four hollow chambers (2 atriums and 2 ventricles) that the blood circulates through and pumps out to the rest of your body!

It's a continuous cycle of pumping blood to and from the heart from the body and pumps about 6000 quarts of blood in a day! (That's over 1,500 gallons)

You can feel your pulse 2 ways

You can find it in your neck (carotid artery)

You can also find it in your wrist (radial artery)

Normal heart rates fall between 60-80 beats per minute depending on a lot of factors (age, weight, fitness level, etc)

So you know the intensity of your physical activity and that it's benefitting you

It lets you know how hard your body is working

The more you exercise, the more you strengthen your heart so it can pump more blood and it needs fewer beats. (Basically, your heart can relax and not work so hard)

The more you exercise=the slower your resting heart rate becomes

Exercise also makes more blood vessels, which means more places for blood to flow and makes circulation more efficient.

Age

gender

body temperature

Physical or emotional stress

How often you exercise

Caffeine

Nervousness