Difference Between Heart Rate & Heart Rhythm

Think of your heart as a four-chambered house, with its own plumbing and electrical systems. The systems work together to keep your body functioning properly, but each is measured differently and has different influences. Your heart rate is the pulse of the blood flowing through the vascular plumbing of your body. It is driven by the electrical activity of your heart, which follows an established rhythm.

Definition

Heart rate is the number of times your heart beats per minute.
Heart rhythm is the repetitive action of your heart--its cadence--which is determined by the prevailing electrical activity.
Assessing the health of your heart means taking both rate and rhythm into consideration. If the rate is too fast, too slow, or is irregular in some other way, health care providers will likely want to examine your heart's rhythm to help explain the abnormality.

Features

The plumbing system of your heart is made up of blood vessels and the blood flowing through them. How quickly the blood flows depends on how fast your heart pumps--and that is determined by the electrical activity of your heart.
Your heart's electricity is supplied by specialized cardiac cells in the right upper chamber of your heart, called the right atrium. Grouped together, the cells form a node known as the sinus node. It is responsible for initiating the spark that spreads through the rest of the cells of the heart, causing the heart muscle to contract and pump blood.

Measurement

You can measure your heart rate with a heart rate monitor, or by taking your pulse. Place two fingers on the inside of your arm, just above your wrist. (See "Resources.") Use a watch or clock and count how many beats you feel for a full minute. Keep track of whether the pulse is regular or irregular.
Determining your heart rhythm requires an electrocardiogram, a test that captures the electrical activity and plots it onto paper for a cardiologist to interpret.

Types

Generally, your heart rate gets slower as you age. A normal rate is 60 to 100 beats per minute, though this may be lower in young adults and people who are extremely physically fit. A heart rate lower than 60 beats per minute is called bradycardia. A heart rate faster than 100 is called tachycardia.
Abnormal heart rhythms are called arrhythmias. A heart that beats too fast or too slow, or irregularly, creates an abnormal heart rhythm--but other abnormalities come from a malfunction in the electrical pathway through the heart. Some arrythmias are harmless, while others can be life-threatening.

Causes

Exercise can cause your heart rate to rise, but so can stress and some medications. Also, since heart rates tend to rise with age, a faster heart rate may become normal for you as you get older.
Fatigue, pain and digestive disorders may slow your heart rate. But well-conditioned athletes may have slower heart rates, which are normal for them.
Cardiac arrhythmias that are not detected through a slow or fast heart rate may show up on an electrocardiogram. Coronary artery disease, heart valve disorders or heart failure can cause these irregular rhythms, but medications also often cause rhythm disturbances.