Scott, an avid 10-year-old soccer player, begins to cough toward the end of the first quarter of his soccer game. The weather is cool and clear. He rests during the second quarter, drinks some water, and the cough gradually abates. He returns to the game in the third quarter and does well. Scott has hay fever and asthma, but only during the spring pollen season.
Scott has a typical case of exercise-induced asthma (EIA), a problem that affects some 8 million people in the United States. Fortunately, with the right combination of exercise modification and medication, sufferers can meet their full exercise potential.
Who Is At Risk?
EIA can occur in any age group, but persons with asthma and other allergies, as in Scott’s case, are especially susceptible. Approximately 80 percent of asthmatics and about 40 percent of people with allergic rhinitis (hay fever) have signs of EIA following exercise.
What Are The Symptoms?
Symptoms can vary from person to person. Typically, they include one or more of the following: wheezing, coughing, shortness of breath, or difficulty in taking a breath.
When Does It Occur?
Symptoms usually start about 5 to 10 minutes after beginning aerobic exercise, and they usually peak about 5 to 10 minutes after stopping exercise. Discomfort and symptoms then diminish over the next 20 to 30 minutes.
Where Does It Occur?
The classic situation that triggers exercise-induced asthma is performing aerobic exercise, such as running, cycling, or other vigorous cardiovascular sports, in cool, dry air. However, EIA may also occur during exercise in hot, dry conditions. Each person can have a unique situation that prompts an attack.
Seeing Your Physician
A physician will counsel asthmatics, or anyone with unexplained exercise-related respiratory symptoms, about the possibility of EIA. With proper precautions and management, EIA should not prevent you from exercising.
Exercising in cool, dry air most consistently causes EIA symptoms. Scientific studies suggest that bronchospasms are triggered by rapid water loss from the airways, or by rapid cooling and rewarming of the airways. Thus, when the weather outside is cool and dry, asthmatics are at less risk for EIA if they exercise indoors or choose outdoor activities with moist environments, such as swimming.
Compared to allergen-induced asthma, EIA symptoms appear suddenly, and upon removal of the triggering stimulus, the symptoms rapidly disappear. Interestingly, if the patient then begins exercise again within an hour, there may be milder or negligible symptoms. Experts recommend a good, lengthy, moderate-intensity warm-up prior to beginning more vigorous exercise.
If you need to document your case, a doctor can perform a test that simulates vigorous aerobic exercise using a treadmill or bicycle in a laboratory. You will be asked to exercise at a high intensity for approximately 5 minutes (or longer if you are a conditioned athlete). Measurements will be taken before, immediately after, and at 5-minute intervals for 30 minutes. Knowing the intensity of exercise that triggers EIA may help you modify your exercise program, for example choosing among sprinting, jogging, and power walking.
Discovering what triggers and complicates EIA is an important part of treatment. Armed with that knowledge, you should be able to achieve your full exercise potential, as have many Olympic athletes with EIA. To diminish attacks, plan a good, lengthy, moderate-intensity warm-up prior to beginning more vigorous exercise.
Your doctor may prescribe medications to ward off EIA attacks. Aerosolized beta-agonists, taken 5 to 30 minutes before exercise, have been shown to be effective. The timing and choice of medication depend on individual response and expected onset and duration of activity. Albuterol (e.g. Proventil) has rapid onset of action, but may cause nervous stimulation in some people. Serevent has a slower onset of action, but a long duration of up to 12 hours. Intal and Tilade may have slower onset of action. Rarely, alternate treatment is required. In such cases, a consultation with an allergist/pulmonologist may be useful.
A viral upper respiratory infection increases your susceptibility to EIA because your airways are already inflamed. You should modify your exercise program whenever you have an upper respiratory infection. During the pollen season, you will need to control your hay fever and asthma so that you can breathe through your nose as long as possible. Warming and humidifying the air you inhale help prevent EIA bronchospasms.
Although the causes are not completely understood, exercise-induced asthma can be managed with early recognition, education, exercise modification and preventive medication. EIA should not prevent anyone from enjoying exercise, whether they are youthful soccer players such as Scott or Olympic athletes going for the gold. EIA should not prevent anyone from enjoying exercise, whether they are youthful soccer players such as Scott or Olympic athletes going for the gold