Skip to main content

Exercise-induced asthma

Medically reviewed by Drugs.com. Last updated on Dec 7, 2022.

Overview

Exercise-induced asthma is when the airways narrow or squeeze during hard physical activity. It causes shortness of breath, wheezing, coughing, and other symptoms during or after exercise.

The medical term for this condition is exercise-induced bronchoconstriction (brong-koh-kun-STRIK-shun). Many people with asthma have exercise-induced bronchoconstriction. But people without asthma also can have it.

Most people with exercise-induced bronchoconstriction can continue to exercise and remain active if they treat symptoms. Treatment includes asthma medicines and taking steps to prevent symptoms before physical activity starts.

Symptoms

Symptoms of exercise-induced bronchoconstriction usually begin during or soon after exercise. These symptoms can last for an hour or longer if untreated. Symptoms include:

When to see a doctor

See your health care provider if you have symptoms of exercise-induced bronchoconstriction. A few conditions can cause similar symptoms, so it's important to get a diagnosis as soon as you can.

Get emergency medical treatment if you have:

Causes

It's not exactly clear what causes exercise-induced bronchoconstriction. For a long time, the cause was thought to be cold air. However, recent studies found dry air to be a more likely culprit. Cold air contains less moisture than warm air. Breathing in cold, dry air dehydrates the air passages. This causes them to constrict, reducing air flow. Other factors, such as chlorine or other fumes, can irritate the lining of the airways and contribute to breathing difficulties as well.

Risk factors

Exercise-induced bronchoconstriction is more likely to occur in:

Factors that can increase the risk of the condition or act as triggers include:

Complications

If not treated, exercise-induced bronchoconstriction can result in:

Diagnosis

To diagnose exercise-induced bronchoconstriction, your health care provider first takes a medical history and does a physical exam. You may have tests to check your lung function and rule out other conditions.

Test of current lung function

Your provider will likely perform a spirometry (spy-ROM-uh-tree) test. This exam shows how well your lungs function when you aren't exercising. A spirometer measures how much air you inhale, how much you exhale and how quickly you exhale.

Your provider might have you repeat the test after you take an inhaled medicine to open your lungs. This medicine is known as a bronchodilator. Your provider compares the results of the two measurements to see whether the bronchodilator improved your airflow. This initial lung function test is important for ruling out chronic asthma as the cause of symptoms.

Exercise challenge tests

During an exercise challenge test, you run on a treadmill or use other stationary exercise equipment to increase your breathing rate.

The exercise needs to be intense enough to trigger your symptoms. If needed, you might be asked to perform a real-life exercise challenge, such as climbing stairs. Spirometry tests before and after the challenge can provide evidence of exercise-induced bronchoconstriction.

Methacholine challenge breathing test

This test involves inhaling an agent, often methacholine, that narrows the airways in some people with exercise-induced bronchoconstriction. Afterward, a spirometry test checks lung function. This test mimics the conditions likely to trigger exercise-induced bronchoconstriction.

Spirometer

A spirometer is a diagnostic device that measures the amount of air you're able to breathe in and out. It also tracks the time it takes you to exhale completely after you take a deep breath.

Treatment

Your health care provider might prescribe medicines to take shortly before exercise or to take daily for long-term control.

Preexercise medicines

If your provider prescribes a medicine to take before exercising, ask how much time you need between taking the medicine and starting the activity.

Long-term control medicines

Your provider may prescribe a long-term control medicine to manage underlying asthma or to control symptoms when preexercise treatment alone doesn't work. These medicines are usually taken daily. They include:

Don't rely only on quick-relief medicines

You also can use preexercise medicines as a quick-relief treatment for symptoms. However, you shouldn't need to use your preexercise inhaler more often than recommended.

Keep a record of:

If you use your inhaler daily or you frequently use it for symptom relief, your provider might adjust your long-term control medication.

Self care

Exercise is an important part of a healthy lifestyle for everyone, including most people with exercise-induced bronchoconstriction. Besides taking your medicine, you can take these steps to prevent or reduce symptoms:

At school

If your child has exercise-induced bronchoconstriction, talk to your health care provider about providing an action plan. This document provides step-by-step instructions for teachers, nurses and coaches that explain:

Alternative medicine

There is limited clinical evidence that any alternative treatments benefit people with exercise-induced bronchoconstriction. For example, it's been suggested that fish oil, vitamin C or vitamin C supplements can help prevent exercise-induced bronchoconstriction, but there isn't enough evidence to show if they're useful.

Preparing for your appointment

You're likely to start by seeing your primary health care provider. Your provider may refer you to someone who specializes in asthma, such as an allergist-immunologist or a pulmonologist.

Be prepared to answer the following questions:

© 1998-2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of use.

Learn more about Exercise-induced asthma

Treatment options

Care guides

Symptoms and treatments

Medicine.com guides (external)