By Robert Grabko, R.P.F.T., B.S.

Athletes with asthma often require medication to help them manage the condition. Because the severity of asthma varies from one athlete to another, pulmonary function and/or exercise challenge studies can help health care providers to customize a treatment plan that may include medication.

Baseline Pulmonary Testing
Athletes in whom asthma is suspect may be asked to perform a baseline pulmonary function study. Doing so helps health care providers to determine whether the athlete has asthma, and if so, to classify the severity of it.

A test known as the “flow volume loop test” is key to the diagnosis of asthma and measurement of its severity. The loop test measures the speed and volume of air in and out of the lungs as well as the condition of the airways. During the test, the health care provider administers medications that either open or tighten the airways so that he or she can observe the impact on the lungs/airways.

If the athlete’s airways are tightened at the beginning of the flow volume loop test, an inhaled bronchodilation medication (dilates the bronchioles) is administered and the affect observed. If the airway opens 20 percent or more with this medication, the airways are said to be “hyper-reactive.”

It normal airflow is revealed at the start of the test, a Methacholine challenge study is performed. When inhaled, Methacholine is a medication that causes airway tightening of more than 20 percent in people who have asthma. The reactivity of the airways is classified as mild, moderate or severe depending on the Methacholine dose needed to trigger airway tightening.

People with only a clinical history of exercise-induced asthma (EIA) generally complete the exercise challenge test. Athletes perform sudden-impact exercise to quickly increase breathing. Oxygen saturation and peak flow measures are monitored at baseline, and during and after exercise. Athletes with EIA generally demonstrate a 15 to 20 percent drop in oxygen saturation and peak flow measures. Depending on the peak flow percentage drop from baseline, the airway reactivity can be classified as mild, moderate or severe.

After Baseline Testing: Determining a Medication or Non-medication Plan
Baseline testing often reveals airway reactivity as controlled or uncontrolled. Techniques such as asthma triggers management, nutrition and hydration, breathing and muscle relaxation and proper warm-up can be taught and pulmonary function testing repeated in a several days to measure improvement, or control, from baseline testing.

If better control of airway reactivity cannot be demonstrated in repeated testing, a customized medication plan is developed and monitored with follow up pulmonary function and exercise challenge testing.

In athletes who experience asthma less than once per week, the only medication indicated is a rescue Albuterol inhaler. This is best taken prior to exercise to prevent airway tightening because once the airway tightens it is often difficult to reopen, even with medication. The rescue inhaler is taken as two puffs with a spacer device on an as-needed basis 30 minutes prior to exercise.

If asthma occurs more than twice per week, a preventive corticosteroid inhaler is recommended. This is taken as two puffs in the morning and evening with a spacer device. As a prescription, it is to be taken consistently every day and will start to be effective at preventing airway tightness after 10 days. The rescue inhaler continues to be used on an as-needed basis.

In athletes with exercise-induced asthma, the medication Cromolyn has been effective in preventing exercise-induced asthma. This is taken as two puffs consistently in the morning and evening and after 10 days to prevent airway tightness. Once Cromolyn is actively in use, it is helpful to take two puffs 30 minutes prior to exercise.

Once the athlete is started on a medication plan, pulmonary function and exercise challenge studies are performed after two weeks to determine how well the airway reactivity is controlled. If needed, adjustments can be made in the medication plan, and follow up pulmonary function and exercise challenge studies will monitor the effectiveness of the medication change.

Once the airway reactivity is brought under control, the athlete can perform VO2 fitness testing to determine anaerobic threshold and VO2 max. An exercise prescription can be put together based on the athlete’s performance goals. For more information, refer to additional Athletes With Asthma resources on this web site.

This information is produced by Athletes With Asthma, a program at Fairview Southdale Hospital dedicated to improving the performance of athletes with asthma.

For an appointment with a respiratory therapist or more information, call 952-924-1451.