The exercise stress test -- also known as an exercise electrocardiogram, treadmill test, graded exercise test, or stress EKG -- is used most often. It lets your doctor know how your heart responds to being pushed. You'll walk on a treadmill .The reaction to stress is produced either by exercise or drug stimulation. The stress test compares the circulation of blood in the heart when the patient is resting and when he is under optimum physical pressure. There are various types of stress tests but the most common of them is the Treadmill stress test.