Test Overview
An exercise electrocardiogram (EKG or ECG) is a test that checks
for changes in your heart while you exercise. Sometimes EKG abnormalities can
be seen only during exercise or while symptoms are present. This test is
sometimes called a "stress test" or a "treadmill test." During an exercise EKG,
you may either walk on a motor-driven treadmill or pedal a stationary
bicycle.
The
heart
is a muscular pump made up of
four
chambers
. The two upper chambers are called atria, and the two lower
chambers are called ventricles. A natural electrical system causes the heart
muscle to contract and pump blood through the heart to the lungs and the rest
of the body.
An exercise EKG translates the heart's electrical activity into
line tracings on paper. The spikes and dips in the line tracings are called
waves. See an illustration of the
EKG
components and intervals
.
A resting EKG is always done before an exercise EKG test, and
results of the resting EKG are compared to the results of the exercise EKG. A
resting EKG may also show a heart problem that would make an exercise EKG
unsafe.