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Do You Need a Stress Test? Here Is What to Know and Expect

Did your health care provider order a stress test? The mere mention of it can cause a wave of stress and worry but fear not! Understanding the basics will hopefully give you peace of mind. 

Stress tests are valuable tools for assessing heart health, and there’s more than one type. With the help of Samuel Unzek, MD, a cardiologist and cardiac imaging specialist with Banner – University Medicine, we break down the three most common types of stress tests, how to prepare for them and what you can expect during the tests.

What is a stress test?

Stress tests show how well your heart works during physical activity. Exercise makes your heart work harder and can reveal problems that might not be noticeable otherwise.

“A greater demand on the heart increases the need for more oxygen,” Dr. Unzek said. “If there are any issues, such as blocked arteries due to coronary artery disease, they may become apparent when the heart is working harder and needs more oxygen.” 

Depending on your overall health and symptoms, your provider might recommend a stress test. The tests will look at:

  • The overall function of your heart.
  • Symptoms of heart disease or blockages.
  • How your heart is working after a medical procedure or intervention.
  • Arrhythmias (irregular heartbeat) that might only show up during exercise.

What are the three main types of stress tests?

There are several stress tests – some more involved than others – but the most common types are exercise electrocardiogram (ECG), stress echocardiography and nuclear stress tests.

Exercise ECG stress test 

An exercise ECG stress test monitors your heart rhythm, blood pressure and breathing while walking on a treadmill or riding a stationary bike. During the study, you will slowly increase your effort until you reach a pre-set target heart rate, experience any symptoms or have changes on the ECG. 

Stress echocardiogram test (stress echo)

The stress echo combines ultrasound imaging and the exercise stress test. “The ultrasound creates images of the heart’s chamber, walls and valves before and after exercise,” Dr. Unzek said.

If you cannot walk or cycle, the test can be done with medication that triggers the same effects of exercise. Medication is given through an IV.

Nuclear stress test

A nuclear stress test includes radioactive material and imaging studies to show how blood is taken up in your heart at rest and during exercise. 

“The process is similar to the exercise stress test, but your provider injects the radioactive tracer into the arm,” Dr. Unzek said. “If you cannot exercise, it can also be done with medication.”

Are stress tests safe?

Stress tests are very safe procedures. However, there is a low risk of complications such as fainting, dizziness, chest pain, irregular heartbeat or heart attack. Your health care team will consider your symptoms, overall health and abilities when deciding which type of heart testing or stress test suits you.

“Safety is the number one priority with these tests,” Dr. Unzek said. “There is always a supervising physician onsite and trained specialists who can handle any situation in case something happens.”

How do I prepare for a stress test?

Preparing for a stress test might involve lifestyle adjustments and following specific instructions from your health care team. The following are general guidelines on what to expect:

  • Clothing: Wear comfortable clothing and walking or running shoes. Leave jewelry and other personal items at home.
  • Medications: Let your provider know about the medications you are taking. They will advise you on whether to continue or temporarily stop certain medicines before the test. Don’t stop any medication without guidance from your provider.
  • Food and drink: Avoid eating or drinking three hours before the test. It is generally not recommended to consume caffeine for at least 12 hours before a nuclear stress test.
  • Exercise: Be prepared for physical activity.

What can I expect during and after the stress test?

Typically, stress tests are performed in a provider’s office or hospital by a trained technician. Test results will be available to your physician the same day or the day after. Here is what to expect during each test:

Stress ECG test

The stress test will take about an hour, but you’ll exercise for 10 to 15 minutes.

Sticky patches called electrodes will be placed on your chest. The patches record your heart rhythm. Wires connect the patches to a computer, which shows the test results. A cuff on your arm will check your blood pressure during the test. 

You’ll either walk on a treadmill or peddle on a bike to increase your heart rate for the test.

When the test is over, you’ll be asked to rest until your heart rate and breathing return to normal. Afterward, you can return to normal activities.

Stress echocardiogram

The stress echocardiogram test will take about two hours, but you’ll exercise for 10 to 15 minutes.

Electrodes will be placed on your chest to monitor your heart. The technician will also use gel and an ultrasound wand on your chest to take detailed images of your heart. Images will be taken before and after the exercise. If a medication is used to increase your heart rate, an IV will be placed in your arm.

After the test, you should be able to return to normal activities.

Nuclear test

The length of the nuclear test varies but may take up to three hours. 

You will either walk or jog on a treadmill or lie on a bed where you are given medication to simulate the effects of exercise. A radioactive dye will be given by IV into your arm. Once your heart has absorbed the dye, your heart will be scanned while you rest and then again after you exercise or receive the medication to mimic exercise. 

When the test is over, you should be able to return to daily activities. The radioactive material breaks down and will be flushed out of your system when you pee. 

Will I need a repeat stress test?

Having a stress test every year is no longer considered an appropriate practice. 

“Annual stress tests have proven ineffective,” Dr. Unzek said. “The benefits may not outweigh the risks or costs. Today, we consider many factors like age, medical history, symptoms and overall health before making recommendations.”

If you’re unsure whether or not you should get another stress test, talk to your health care provider or cardiologist, who can help determine when stress tests are appropriate for you.


Getting a stress test might sound intimidating, but it is an important and generally simple step in understanding your heart health. By knowing the basics of stress tests, you can confidently navigate the process. 

Contact your health care provider or a Banner Health specialist with additional questions or concerns. 

For more heart-related articles, check out:

Heart Health Hypertension