What is it? 
An exercise test usually involves walking or running on a treadmill – or pedaling a cycle – while the effect on the heart and blood pressure is measured.

Why is it done? 
An exercise test tells a pediatric cardiologist how well the heart works and how well it adjusts to different levels of activity.  Exercise testing is the best way to get this information.  Changes a doctor may want to evaluate include heart rate, heart rhythm, blood pressure, symptoms and heart function.

How is it done? 
Your child will exercise on a treadmill or special cycle.  He or she should wear comfortable clothing or gym clothes and bring running shoes.  Your child should not take the test immediately after a heavy meal.  Please encourage your child to cooperate fully.  Sometimes pre-school children can be adequately tested, because some are large enough and mature enough to cooperate.

After a brief history is taken, a technician will apply patches called electrodes on your child’s arms and chest.  The electrodes are connected by wires to an electrocardiograph (ECG or EKG) machine.  The wires are usually held in place by a net shirt or a wrap so they won’t fall off.  A blood pressure cuff is also put on your child’s arm.

At times, your physician may want information about your child’s ability to exchange oxygen.  Your child will then be asked to breathe in and out of a mouthpiece, like a snorkel.  A soft clip will be placed on your child’s nose.  Additional testing of lung function before and after exercise may be done with the exercise test to check your child for other conditions such as asthma.

A resting ECG and blood pressure will be taken first.  Your child then walks on the treadmill or pedals the cycle. (Exercise increases by speeding up the treadmill and increasing its steepness, or by making the cycle harder to pedal.)  Your child will be encouraged to exercise as long as possible.  A pediatric cardiologist or other qualified person will carefully watch the ECG and blood pressure during the test and ask your child about the level of exertion throughout the test.  After your child has reached maximal exercise, or if abnormal changes are noted on the ECG or in blood pressure, the test will be stopped.  Then your child will lie or sit down, and additional measurements will be taken during the rest period.  The entire test should last less than one hour.

During some exercise tests, extra information may be obtained by using an "echo" or Doppler test at the same time.  Your pediatric cardiologist can tell you about these additional tests if they’ll be used.

Does it hurt? 
No.  But since this is a test of maximal effort, expect some shortness of breath and muscle fatigue.  Rarely nausea can occur after reaching maximum exercise.  Sometimes there’s slight discomfort when the patches are put on or taken off (much like a bandage being attached or removed).

Is it harmful? 
Exercise usually isn’t harmful.  While there are rare risks to exercise testing, these usually relate to certain heart conditions.  Your cardiologist will discuss any risks of the test which are specific to your child before the test is scheduled.  This test is done to see if your child develops problems during exercise.  Careful monitoring is done to detect any problems.

Prepared by the Committee on Congenital Cardiac Defects of the Council on Cardiovascular Disease in the Young