An exercise stress test can help determine whether significant blockages in the coronary arteries are interfering with blood flow during physical activity. Although the test carries a very small risk of a heart attack or cardiac arrest, you’ll be carefully monitored and treated immediately if any serious problems occur.

During the test, you walk on a treadmill or pedal a stationary bicycle. The speed and incline of the treadmill or the resistance of the bicycle is gradually increased until you reach your target heart rate. The stress test is stopped early if you

  • become fatigued
  • experience symptoms such as chest pain, shortness of breath or dizziness
  • develop an irregular heartbeat or very high blood pressure;
  • or the ECG shows evidence of poor blood flow to the heart.

Some people—often those who are elderly or frail—can't walk on a treadmill or pedal a bicycle. For these individuals, drugs such as dobutamine are used to simulate the effects of physical exercise on the heart. While you’re seated or lying down, the exercise-simulating drug is injected into a vein and the electrical signals from your heart are monitored.

There's a very small risk of having a heart attack or cardiac arrest while undergoing the test.

Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Publication Review By: the Editorial Staff at

Published: 10 Jul 2013

Last Modified: 10 Jul 2013