Exercise-induced asthma: wheeze, cough and breathlessness with exercise

It is normal to breathe faster and deeper during exercise. When breathing becomes difficult, with coughing, wheezing or a tight chest, exercise may be acting as an asthma trigger. The NHS lists exercise among the things that can set off asthma symptoms, alongside air pollution, cold air and allergens such as pollen, dust, mould or animals.

Asthma + Lung UK separates three situations. In one, exercise reveals asthma that is not well controlled. In another, asthma is generally well controlled but exercise still triggers symptoms, which it calls exercise-induced asthma. In a third, people without asthma get airway narrowing with exercise, called exercise-induced bronchoconstriction. Distinguishing them matters because the first usually calls for a review of everyday asthma treatment, whereas the third may be managed with a reliever before exercise.

The Cambridge University Hospitals leaflet for children and young people describes exercise-induced bronchoconstriction as the small airways narrowing during exercise, making it harder to breathe, and states that this can happen even if you do not have asthma.

Asthma + Lung UK explains that during exercise people tend to breathe through the mouth more than the nose, so the air they inhale is less warmed and moistened. For some people with asthma, colder, drier air makes the airways tighten and narrow, which brings on cough, wheeze and breathlessness.

The same page points out that it can be difficult to tell whether exercise itself is the trigger, or something encountered while exercising. Outdoors, pollution and pollen may be responsible; in a gym or exercising on the floor, dust; in swimming, chlorine in the pool; and hot, cold or sudden changes in weather can also play a part. It suggests keeping a symptom calendar to spot patterns.

It also notes that wheeze or breathlessness during exercise can be due to general lack of fitness or being overweight rather than asthma. That is one reason a proper assessment is worthwhile rather than assuming.

Asthma + Lung UK lists coughing, wheezing, a tight chest and breathlessness as the signs that exercise may be a trigger. The Cambridge leaflet describes coughing when or after running, wheezing, a tight chest, and feeling short of breath or tired too fast, and says that symptoms are often worse after stopping, typically 10 to 15 minutes later, usually improving within 30 to 60 minutes.

Because asthma symptoms in general vary, the NHS notes they can be mild or severe, usually come and go, and may be worse at night and early in the morning. Night-time or early-morning symptoms in someone who also gets exercise symptoms suggest the underlying asthma is not settled.

The NHS says a GP or nurse will ask questions and listen to the chest, and that a simple breathing test, sometimes a blood test, and a peak flow meter used at home for a few weeks may be used. It adds that asthma can take time to diagnose because symptoms vary and breathing problems can have different causes. NHS inform lists tests such as exhaled nitric oxide or blood tests for airway inflammation, spirometry, peak flow, allergy tests and airways responsiveness testing.

For exercise-related symptoms, a description of when they start and stop, what the weather and setting were, and whether a reliever helped is very useful. Asthma + Lung UK suggests seeing a GP or nurse if symptoms are worse with exercise or if extra doses of reliever are needed. Guides on spirometry and peak flow diaries on this site explain what those tests involve.

Asthma + Lung UK says a GP or nurse can review asthma medicines, check inhaler technique, update the asthma action plan, consider add-on treatment such as a long-acting bronchodilator or montelukast for people whose symptoms are only triggered by exercise, and help manage other triggers. It stresses always carrying a reliever inhaler, and taking a preventer or MART inhaler every day as prescribed, since this makes airways less likely to react to cold, dry air or allergens during exercise.

The Cambridge leaflet suggests a 10 to 15 minute warm-up, using a prescribed inhaler before PE or sport, and avoiding triggers such as cold air, pollution or strong smells. These are written for children and young people but the principles are similar for adults.

The NHS encourages people with asthma to exercise regularly and to ask a doctor or nurse for advice on exercising safely if exercise triggers symptoms. Medicines named here are for information; which inhaler and when to take it is a prescriber's decision.

• Carry the reliever inhaler to every session, and check it is in date.

• Take preventer or MART inhalers daily as prescribed, not only before exercise.

• Warm up gradually, and consider a gentle cool-down.

• Note where and when symptoms occur, as pollen, pollution, chlorine or cold air may be the real trigger.

• Ask for an updated asthma action plan if exercise needs are changing.

The NHS advises sitting up straight, staying calm and using the reliever inhaler. With a blue reliever inhaler that means 1 puff every 30 to 60 seconds until you feel better, up to a maximum of 10 puffs, ideally with a spacer; for an AIR or MART inhaler it is 1 puff every 1 to 3 minutes up to a maximum of 6 puffs, unless your personal action plan says otherwise.

Call 999 if you or someone else feels worse at any time, does not feel better after the maximum dose, or has no inhaler. NHS inform lists severe difficulty breathing, such as struggling to speak or gasping, severe chest pain, drowsiness, and pale, blue or grey lips or skin as emergency signs. The NHS also asks anyone who has had an attack and recovered to see a GP within 2 days.

Most people with exercise-triggered symptoms are assessed in general practice by a GP or asthma nurse. Further testing or specialist review through a respiratory clinic is usually considered when the diagnosis is unclear, when treatment is not controlling symptoms, or for competitive athletes who need formal testing.

Some athletes and parents of young sportspeople choose a private respiratory or sports medicine appointment for a faster exercise challenge or lung function test. Asthma + Lung UK notes that breathlessness during exercise can have causes other than asthma, so a clear explanation of what was tested and why is worth asking for in either setting.