Causes and management of exercise induced asthma
An asthma attack can be triggered by doing exercise
This happens because during exercise you breathe through your mouth and colder drier air can affect your lungs
You can prevent exercise-induced asthma using techniques and inhaler treatments
You should still exercise, even if you’re worried about exercise-induced asthma
What is exercise-induced asthma?
Exercise-induced asthma is when you get asthma symptoms when you exercise. You might not have asthma at any other time, or you might notice that your normal asthma symptoms are worse or come on more when you exercise.
Why does exercise trigger asthma?
Exercise, or physical exertion, can induce asthma symptoms. This is because the way we breathe changes when we exercise.
In normal breathing, we breathe mostly through our noses. The air we inhale travels through our nasal passages, getting warm and moist before reaching our lungs.
When we breathe during exercise, it tends to be through our mouths rather than our noses. This means that the air we inhale is cooler and drier. Cold and dry air can be a shock to our airways, which are very sensitive to any change in temperature or humidity. The muscles in the airways react by narrowing or closing in, thereby triggering the asthma symptoms.
The symptoms of exercise-induced asthma are very similar to those of chronic asthma, or to a normal asthma attack. They include:
- a tight chest, and wheezing
- gasping or feeling like you can’t breathe
- not being able to speak in full sentences
- difficulty finishing exercise
Breathing heavily, needing to catch your breath and feeling your heart racing are normal feelings when you’re exercising. But if you notice any of the symptoms in the list above, this could be due to exercise-induced asthma.
If you think that you might have exercise-induced asthma or your normal asthma symptoms are worse when you exercise, you should see your GP or asthma nurse so that they can recommend other treatments.
How can I prevent exercise-induced asthma?
Sometimes, asthma attacks are unavoidable. But there are some things you can do to help prevent exercise-induced asthma:
- Use your preventative asthma inhaler 10-15 minutes before exercising
- Remember to warm up and warm down properly
- If it is very cold, and you have to exercise outdoors, wear a scarf or mask to cover your mouth and nose
- If you have allergies to pollen and the pollen count is high, avoid exercising outdoors
How do you treat exercise-induced asthma?
You should treat the symptoms of exercise-induced asthma in the same way as you would treat your normal asthma symptoms, or an asthma attack. Try to remain calm, and use your reliever inhaler to relieve your symptoms, taking 1 puff of your inhaler every 30 to 60 seconds for a maximum of 10 puffs.
If your symptoms do not improve, or you are worried at any point, dial 999 for an ambulance and repeat the first steps while waiting for medical assistance.
Your GP or asthma nurse might recommend that you start using a preventer inhaler or change to a different one to try to stop these symptoms from happening.
Should I exercise if I have asthma?
Yes! There is no reason you should avoid exercise or physical activity if you have asthma. In fact, exercising regularly will help your overall health, and may even improve your symptoms.
If you follow the steps above for preventing exercise-induced asthma, you should be able to exercise normally, without the symptoms of an attack.
Exercise-induced bronchoconstriction: diagnosis and management, American family physician [accessed February 2023]
Exercise-induced asthma: fresh insights and an overview, Malaysian family physician [accessed February 2023]
Asthma, National Health Service [accessed February 2023]
Exercise-induced asthma, IQWiG (Institute for Quality and Efficiency in Health Care) [accessed February 2023]
Preventer inhalers, Asthma and Lung UK [accessed February 2023]