If you want to measure your cardiovascular condition or maximum heart rate, you can take an exercise stress test on a treadmill. Health care professionals also use stress tests to evaluate patients' physical condition and to diagnose problems. Treadmill tests are probably the most well-known, but an exercise stress test can be performed using other equipment such as a stationary bicycle
Purpose
Physicians use exercise stress tests on treadmills for several reasons. Chiefly, stress tests are used for evaluations related to coronary artery and heart diseases. In some cases, the purpose is to diagnose possible problems or to predict the risk of heart or coronary artery disease.
The exercise stress test is also an effective way to evaluate the results of treatment and the status of existing conditions. Athletes and trainers use exercise stress tests to measure maximum heart rate and the state of a competitor's endurance. You can also measure VO2, which is the rate at which the lungs can absorb oxygen and transfer it to the body through the bloodstream.
Procedure
When you take an exercise stress test on a treadmill, you start at a slow walk, possibly with the treadmill set to an incline. Doctors attach electrodes so your heart function can be monitored by an ECG machine, plus a blood pressure cuff. Depending on the specific goal of the test, you may be asked to breathe into a tube. You can stop the test at any time if necessary.
Once the treadmill test is finished, doctors may take more measurements while you recover. The test is normally terminated based on blood pressure or heart rate readings, but can be stopped if you experience chest pain or the ECG indicates a problem. However, when an athlete takes a stress test, she may continue until completely fatigued and exerting maximum effort.
Protocol
There are several formats, called protocols, for exercise stress tests. The Bruce Treadmill test is the most widely used. You begin by walking for three minutes at a pace of 1.7 mph on a treadmill set to a 10-percent incline. Every three minutes thereafter, the speed increases and the incline goes up an additional 2 percent.
There can be as many as 10 stages, though the fastest and steepest are rarely used except for athletes in top physical condition. Modified versions of the Bruce protocol are sometimes used. For example, an elderly patient may start at 1.7 mph but with no incline.
Preparation
When you plan to take a treadmill stress test, you should not eat anything, smoke or drink alcohol for at least three hours beforehand. Avoid drinking anything with caffeine. Wear shoes that are comfortable and suited for running. Your clothes should be loose-fitting and comfortable as well. Tell your doctor about any medications you are taking. Treadmill stress tests for medical reasons may not be particularly demanding. Tests to determine athletic performance often are, and you should be in good physical condition before attempting one.
