There's more than one reason your doctor may want you to take a stress test. Cardiologist Steven Longobardi explains, "An evaluation of chest pain, evaluation of palpitations, so it does not, it's not worrisome if a stress test is ordered, it's just one test that helps the physician get better standardized care for the patient."

This test allows doctors to find out how well your heart handles work. If you can't walk the doctor can use a drug to effect the blood supply to the heart and simulate the effects of exercise. Heart patient Deborah Brasher says that "I need to have some surgery on my knee and I'm not able to walk on the treadmill, so we're having to do this instead."

Dr. Longobardi says "For people who walk, generally it requires a treadmill, a standard treadmill test with varying stage, varying speeds."

Dr. Longobardi also says that as your body works harder during this test, it requires more oxygen, thus requiring your heart to pump more blood. At the end of this test you'll be able to tell whether the arteries are supplying enough blood to the heart. "To push the patient to the limit to be sure that under extreme conditions the heart can withstand it."

Depending upon the results of the exercise stress test, your physician may recommend more tests or a cardiac catheterization.

Typically it is recommended that patient's refrain from using tobacco, certain prescription and nonprescription drugs, and alcohol or caffeine for 24 hours before the test.