An exercise tolerance test, also known as a stress test, checks your heart's activity as you exercise. The test should only take around 30 minutes, and you will have have two cardiac physiologists in your appointment.

Your doctor may refer you for this test if you have had a heart operation or are experiencing:

  • chest pain

  • breathlessness

  • palpitation

  • fainting as you exercise

This test will let your doctor see how your heart is working. You may also have the test as part of our many screening programmes for coronary artery disease or sudden cardiac death.

The test

This test checks your heart's activity at rest and during exercise.

You need to arrive at least 10 minutes before your appointment. If you are more than 10 minutes late, we may have to cancel your appointment as the test is around 30 minutes and may cause delays to other patients. If you have a condition (temporary or permanent) that could affect you walking on a treadmill, you need to tell us. It is better to do this when you are first referred for the test, and if you have the test, let your cardiac physiologist know.

Make sure you are well rested that day and try to avoid any heavy exercise. If you are feeling unwell (with something like a cold or chest infection) you need to let us know. We will need to reschedule your test to make sure the results are accurate.

It is really important to do your absolute best in this test. We want you to put in as much effort as you can, and to continue until you are exhausted. If you feel like this is not possible, contact us before the test.

One of the cardiac physiologists will put ten sticky patches (electrodes) on your chest. These connect to the ECG machine and will record your heart's rhythm and electrical activity.

We will first take a resting ECG and put a blood pressure cuff on your arm. During the test, we will take your blood pressure every three minutes.

When you get on the treadmill, you will start walking slowly at first. After every three minutes, we will increase the speed and slope of the machine. This will make your heart and body work faster. You should keep going as long as you can, but after 15 minutes, we will start to slow down the treadmill. If you need to, you can ask for the treadmill to be stopped at any point during the test, but try to do as much as you can. Make sure you wait until the treadmill has completely stopped before stepping off.

For information about how to prepare for this test and how to contact the team, click the 'Information' tab. 

Ion channelopathies are a group of rare genetic conditions, caused by a gene

Cardiomyopathy is a disease that affects the heart muscle. Cardiomyopathy can often be caused by a genetic mutation, and can therefore run in families affecting one or many members, at any age.

Coronary artery disease is also known as 'ischaemic heart disease' and occurs when a fatty substance called 'atheroma' develops on the inside of an artery.

Preparing for the test

Make sure you wear comfortable clothing for your appointment and wear flat shoes (ideally trainers) that will not slip off your feet. You will have the opportunity to have a shower after the test, so if you want to do this, bring along a change of clothes and toiletries.

Continue taking medications as normal, unless your doctor has told you otherwise. You can also take your breathing medications before the test as normal.

If you smoke, try not to for at least eight hours before the test. You should try not to eat a heavy meal for at least two hours beforehand. You should also not drink any drinks with caffeine in them before the test. This will help us take accurate measurements.

After the test

You will be able to freshen up or have a shower after the test at the hospital, but make sure you do not have a hot shower for at least an hour after the test. When you exercise, your blood vessels expand, so they need time to return to normal. A hot shower may expand them further, causing low blood pressure and dizziness.

You will be able to eat and drink as normal straight after the test. Depending on how you feel, you will be able to go back to your normal routine. But you can also rest and take it easy if you need to.

Your cardiac physiologist will look at your test results and produce a report. This report is uploaded to the electronic patient record (EPR) system, ready for your doctor to review at your next appointment.

Contact our cardiac physiologists

Royal Brompton Hospital

Telephone: 020 7351 8641

Harefield Hospital 

Telephone: 01895 828 566