Your child will blow into a spirometer to measure how fast he or she is able to move air in and out of the lungs.

After successful completion, your child will run on a treadmill for four to eight minutes to achieve maximum heart rate.

Your child will be placed on an oxygen and heart rate monitor to allow continuous monitoring. While running, he or she will be asked to rate on a scale of 1-10 the level of difficulty breathing.

After exercise, your child will continue to perform a minimum of two spirometry maneuvers every five minutes for 30 minutes. If there is a significant change in your child's lung function, he or she will be treated with a bronchodilator before discharge.

The test takes about 1½ to 2 hours. Timing includes explanation and practice testing.

Your child will need to wear comfortable, loose and appropriately fitting clothes and gym shoes (required).

Your child should not eat three hours before testing; however he or she may drink clear liquids one hour prior to testing. Your child should avoid caffeinated products like coffee, tea and cola drinks; chocolate; added sugar; and over-the-counter sinus or cold medications. No smoking for 24 hours before testing.

For optimal testing, it is recommended that certain medications NOT be taken before the test. Download a patient instruction sheet about medications. (.pdf) However, if you have concerns about not taking these medications, contact your doctor.

There are no side effects and your child may resume normal activities after testing.