What is an exercise endurance test?

An exercise tolerance test (also called a stress test) shows your heart’s ability to handle physical activity.While exercising on a treadmill or stationary bike, your healthcare provider will measure your heart rate, blood pressure, and breathing while monitoring ECG (ECG), a test that records electrical signals from the heart.

Exercise tolerance tests are often used to detect certain heart conditions or to determine a safe level of exercise in people with heart disease.

This article provides an overview of what an exercise endurance test is about and how to interpret the results of the test.

Purpose of Exercise Endurance Testing

An exercise tolerance test assesses how hard your heart is working under the stress of physical activity.

When we exercise, our heart beats more rapidly to pump blood and oxygen throughout the body. Certain heart conditions are often easier to detect when your heart is working hard because the heart may appear to be working normally at rest.

After connecting a patient to a blood pressure cuff and EKG during a workout on a treadmill or stationary bike, a healthcare provider can monitor your:

  • heart rate
  • blood pressure
  • breathe
  • effort level

Not everyone needs an exercise tolerance test. They are mainly used to detect heart disease or to monitor pre-existing heart disease. For example, a healthcare provider might recommend this test:

  • If you have symptoms such as chest pain or shortness of breath that may indicate heart disease
  • If you have an irregular heartbeat
  • Identifying a safe exercise program for patients recovering from heart surgery
  • See if the heart treatment you are receiving is working well


An exercise tolerance test can demonstrate your heart’s ability to withstand physical activity. This in-office exam is often used to help detect heart disease and determine appropriate treatment or exercise programs for people with existing heart disease.

Limitations of Exercise Endurance Testing

As with any medical test, the exercise tolerance test has some limitations. E.g:

  • Exercise tolerance tests can help detect blocked arteries in coronary artery disease, but they cannot predict things like the degree of arterial thickening or whether and when a person is likely to have a heart attack.
  • Exercise endurance test results are not always 100% accurate and may vary based on the equipment used, the experience of the healthcare professional conducting the test, and other factors. Some people may get false-positive results, indicating no heart disease.

With this in mind, your healthcare provider will typically use the results of an exercise tolerance test along with other information (such as your symptoms, medical history, and the results of other tests) to make a decision or diagnosis.

Exercise Testing Recommendations

U.S. Preventive Services Task Force Recommendations be opposed to Routine exercise tolerance testing is done in people who do not have any heart symptoms and who are at low risk of heart disease. This is because the risk of a false positive result could lead to unnecessary further testing, treatment or concern.

Risks of Exercise Endurance Testing

The exercise tolerance test is a relatively safe test.

That said, sometimes raising your heart rate with exercise can cause symptoms like dizziness, chest pain, or nausea. A healthcare provider will monitor you closely throughout the test to reduce the chance of this happening and to deal quickly with any issues that may arise.

In addition, people with certain pre-existing heart conditions may experience complications such as irregular heartbeats and even heart attacks.To be safe, your healthcare provider may no Exercise tolerance testing is recommended if you have any of the following heart conditions:

  • unstable angina pectoris (chest discomfort caused by poor blood flow)
  • out of control Arrhythmia (irregular heartbeat)
  • pulmonary hypertension (a type of high blood pressure)
  • serious aortic valve stenosis (narrowing of the great arteries)
  • Congestive heart failure (a condition in which the heart cannot pump blood properly)
  • pulmonary embolism (clot in the pulmonary artery)
  • aortic dissection (tear of a large artery)
  • another acute disease

before testing

The exercise tolerance test does not require much preparation. Your healthcare provider will give you a set of guidelines to follow, which may include the following instructions:

  • Avoid eating large meals or drinking anything other than water for a few hours after the test.
  • Avoid caffeine the day before the test.
  • Wear loose-fitting clothing and comfortable walking shoes.
  • Continue to take any usual medicines unless your healthcare provider advises otherwise.

During the test

Exercise tolerance testing is done in a healthcare provider’s office or hospital and is supervised by a medical professional. They are relatively quick and painless, minus any slight discomfort you may feel while exercising. The test itself takes about 15-20 minutes.

Here’s what you can expect:

  1. Equipment used will include treadmills or exercise bikes, connected to electrode (wire), blood pressure cuff, and pulse oximeter to measure blood oxygen levels.
  2. Small electrodes will be attached to the skin on your chest or shoulder and connected to an EKG machine to measure your heartbeat and heart waves. Additionally, the blood pressure cuff will wrap around your arm and the pulse oximeter sensor will clip on your finger.
  3. You will then be asked to start exercising at an easy pace on the treadmill or bike. The speed and incline gradually increase as the ECG monitors how your body and heart respond to the stress of exercise.
  4. You may be asked to breathe through a mouthpiece, which will measure the amount of air you exhale.

Your ECG, heart rate, blood pressure and breathing will be monitored and recorded before, during and after the test.

after test

After the test, you can sit or lie down for a few minutes until your heart rate returns to its normal resting state. You may be offered a glass of water or a towel as you cool off.

If your blood pressure rises significantly during the test, or if your healthcare provider notices any other related symptoms, you may be monitored for a few more minutes.

Once cleared, you are free to go home and wait for test results, which will usually be back within a few days.

Interpreting the results of an exercise endurance test

After the test is complete, your healthcare provider will review the results. They will evaluate the following factors:

  • your ECG reading
  • blood pressure changes
  • heartbeat changes
  • any symptoms reported or noted during the test
  • Your estimated athletic ability

After summarizing the items, your provider will review the results with you and provide conclusions based on their interpretation. Possible outcomes include:

  • Positive (or abnormal): This means the test found underlying evidence of heart disease.
  • Negative (or normal): This means the test did not find any evidence of heart disease.
  • Indeterminate or unexplained: This indicates that the test cannot determine the presence of heart disease. In this case, the device may be malfunctioning, or you may not be able to complete the test.
  • Goals reached: If you take a test after a heart diagnosis or surgery to help develop a safe exercise plan, your healthcare provider may have set some fitness goals that you can reach.


A stress test provides your healthcare provider with important information about the possibility of heart problems and recommends next steps for you. Ultimately, your healthcare provider is the best source of information for interpreting stress test results.

follow up

Depending on the results​​, your healthcare provider may want to discuss further testing, alternative testing, or treatment options with you.

In some cases, additional appointments or tests may be required:

  • Confirm your exercise tolerance test results
  • Seek more information after your exercise tolerance test results

Follow-up tests may include:

  • MRI (magnetic resonance imaging) heart scan to evaluate the structure of your heart
  • CT coronary scan to see the arteries that supply blood to the heart
  • myocardium Perfusion scan to provide a visual representation of how the heart is pumping
  • nuclear stress test to measure blood flow to the heart


An exercise tolerance test is a way to record your heart’s response to the stress of physical activity. It measures your heart’s electrical activity, heart rate, blood pressure and breathing while you’re on a treadmill or exercise bike.

Exercise tolerance testing can be used to diagnose certain heart conditions, monitor recovery from a heart attack, or develop an appropriate fitness program for heart or surgery patients. Your healthcare provider may recommend this test if you report underlying heart disease symptoms, such as chest pain or shortness of breath. This test is generally not recommended for people with a low risk of heart disease.

VigorTip words

An exercise tolerance test is one tool to help diagnose certain types of heart disease and monitor existing heart disease, but it’s not the only tool available. If you have symptoms that you think may be related to your heart, or if you have had an exercise tolerance test but don’t know the results, contact your healthcare provider for help or a second opinion.

Check out the American Heart Association website for a list of helpful questions to ask your healthcare provider, as well as other resources for patients seeking help.