Do you have problems with coughing, wheezing, or chest tightness when you exercise? Do you feel very tired and short of breath when you exert yourself? Some people wrongly believe that they are just out of shape when, in fact, they may have exercise-induced asthma. About 18 million Americans have asthma and, of those, 80% will have increased symptoms with exercise. In non-asthmatics, up to 15% experience asthma symptoms with exercise and 40% of people with nasal allergies may experience exercise-induced asthma symptoms.
What is Exercise-Induced Asthma?
Exercise-induced asthma (EIA) is a reaction of the lungs caused by exercise. The bronchial tubes become irritated and constrict, also known as bronchospasm. Excess mucus is also formed contributing to the blockage of the airway and congestion. It is thought that when you exercise the airway is cooled and dried rapidly which sets off the reaction in some people. Although chronic asthma sufferers are more likely to have EIA, the presence of EIA does not lead to chronic asthma.
Symptoms and Triggers
Symptoms of EIA include shortness of breath during or after exercise, coughing, wheezing, chest tightness or pain, and extreme fatigue. Symptoms usually start within 5-20 minutes after starting exercise and may last for 30-60 minutes. Sometimes symptoms start only after activity has stopped however. “Locker room cough”, or a cough that occurs after exercise, is a common form of exercise induced asthma. Shortness of breath, from poor conditioning, usually resolve within a few minutes of rest. People with EIA are overly sensitive to sudden changes in temperature and humidity. Colder, drier air is usually more of a problem. Nasal breathing helps warm and humidify the air you breathe so mouth-breathing with exercise reduces the moisture and humidity of the air that reaches your lungs. Air pollution, high pollen counts, and viral upper respiratory infections can also worsen wheezing with exercise.
You should talk to your doctor if you think you may have EIA. You will need a good history and physical which often leads to the diagnosis. You may have a resting lung function test to make sure you have no chronic asthma. You may also have a breathing test after exercise, although this test may not be positive in everyone with EIA. A trial of bronchodilator therapy prior to exercise may be used to help determine whether you have EIA. Chest pain may be a symptom of EIA, but it is important for your doctor to rule out cardiovascular disease as well.
Treatment and Practical Tips
There are things that you can do to reduce the chance of having symptoms. Staying out of cold, dry air is a big factor so train indoors if possible. If you do exercise in the cold, try to breathe through the nose as much as possible, wear a mask or scarf, and avoid exercise in the cold if you have a respiratory infection. Warming up 45-60 minutes before training or playing may help. Taking frequent, short breaks can help. Avoid training or playing outside on days with high pollution or pollen counts. Certain sports are tolerated more than others. Swimming is usually tolerated well due to the humidity of a pool. Lower intensity sports like golf, baseball, and weight lifting are better tolerated. Sports with short bursts of energy such as baseball, football, wrestling, gymnastics, and short-term tack events are better tolerated than soccer, basketball, hockey, skiing, and long-distance running. Always have your asthma medications with you!
The first step of treatment is the use of an inhaled short-acting bronchodilator medicine 15-20 minutes before exercise. These include albuterol, pirbuterol, and levalbuterol and are effective in 80-90% of patients, have a rapid onset of action, and last for 4-6 hours. If symptoms are not controlled by these short-acting medications, a daily medication may have to be used to prevent inflammation and responsiveness of the airway.
Most importantly, you should be evaluated and continue to exercise. Exercise and training will improve fitness, reduce the amount of breathing needed with exercise, and allow you to exert yourself at a higher intensity before symptoms begin.