Exercise is a common trigger of asthma symptoms. It often causes the airways to narrow, which leads to breathing problems. Usually, exercise is 1 of several factors that can trigger symptoms for people with asthma. For some people, exercise may be the only trigger.
Most people with exercise-induced asthma can still stay active. Asthma drugs and adjustments to your exercise routine can help control symptoms triggered by exercise.
Why does exercise trigger asthma symptoms?
Asthma triggered by exercise is called exercise-induced asthma. During normal breathing, the nose warms and humidifies inhaled air. But during exercise, most people breathe heavily through their mouth. This causes the inhaled air to be colder and drier during exercise.1,2
Through this process, the airways lose water and heat. Losing water and heat causes changes that lead to inflammation and narrowing. This makes it harder to breathe and causes symptoms of asthma. Symptoms usually start 2 to 5 minutes after exercise, peak after 10 minutes, and go away after an hour.1,2
Outdoor exercise also exposes people to other asthma triggers. Athletes are often exposed to triggers such as:3
- Cold and dry air
- Air pollution
- Outdoor allergens
- Chlorine in swimming pools
- Chemicals from ice cleaning equipment
How common is exercise-induced asthma?
Exercise is a trigger for about 90 percent of people with asthma. But exercise can cause airway narrowing even in people without asthma.3
Between 5 to 20 percent of people have asthma symptoms caused only by exercise. It is much more common in elite athletes. Swimmers, runners, bikers, and winter athletes have the highest risk. This may be because of higher exposure to other triggers, such as cold air and chlorine products.1,2
What types of exercises cause more asthma symptoms?
Endurance and winter sports have the highest risk of causing asthma symptoms. Long-duration exercise and low air temperatures are more likely to cause airway inflammation and narrowing. Some sports and exercises that carry a high risk include:1
- Long-distance running
- Ice skating
- Ice hockey
What types of exercises are safe for people with asthma?
People with asthma can still exercise and stay active. Regular physical activity is important for your overall physical and mental health. Exercise can help you maintain a healthy body weight, which may reduce asthma symptoms. If your asthma is well-controlled, most physical activities are safe.1
Athletes with asthma still compete on a high level. In fact, athletes with asthma have won many medals at recent Olympic Games. With an early diagnosis and careful treatment, people with asthma can still safely compete.4
Even still, it may be helpful to choose sports and exercises that have a low risk of causing symptoms. These are usually exercises with a short physical duration (less than 5 to 8 minutes of effort), including:1
- Track and field exercises such as sprinting, hurdling, jumping, and throwing
- Team sports such as football, basketball, and baseball
- Weight lifting
- Martial arts
You can also alter your exercise routine to lower the risk of asthma symptoms. Ways to reduce symptoms triggered by exercise include:1,5
- Do 15 minutes of warm-up before your regular exercise
- Breathe through your nose as much as possible
- Wear a face mask when exercising in cold, dry weather
- Avoid outdoor exercise when pollen counts and air pollution are high
Talk to your doctor about what types of exercise are safe for you. They can help suggest ways to reduce symptoms during exercise.
Treatment for exercise-induced asthma
There are medicines that can help you prevent and treat exercise-induced asthma. Your doctor may recommend that you use your rescue inhaler 15 to 30 minutes before exercising.6
If you are in a sport with daily practice or you exercise vigorously every day, your doctor may place you on a daily controller medicine if you do not already take one.6