Beating Exercise-Induced Asthma - Part 2

by Eli Hendel, M.D. Medical Reviewer

In part one we explored a study that confirmed that exercise can be truly beneficial to a person with asthma. In one type of asthma, however, the discussion is a bit more complicated.

Exercise induced asthma is one condition that can modify the physical activities of asthmatics. It is defined as “the occurrence of shortness of breath or cough, usually after the cessation of exercise.” The symptoms actually start once the exercise ends. During exercise there is a “refractory period,” where the airways are dilated due to the increase of adrenaline-like substances produced during the physical effort which has a bronchodilator effect. The higher the intensity of the exercise performed, the greater the bronchodilator effect.

The problems develop after exercise ends, when there is cooling and drying of the inner mucosa of the airways. This phenomenon is caused by heat and water losses during exercise, specifically related to hyperventilation. Every exerciser will experience this process, but asthmatics have abnormally hyper-reactive airways. The hyperactivity is due to specific sensitized cells. These lymphocyte or TH cells secrete inflammatory substances called leukotrienes and interleukins. The production of these inflammatory substances, differentiate asthmatics from other healthy exercisers.

Medications make the difference

In exercise-induced asthma you need drugs that specifically address this process. These medications act specifically on those substances, limiting them. One such medication in this class of drugs is Montelukast (Singulair). Ironically, it’s actually not the most commonly used medication for exercise-induced asthma. Typically, individuals will use a short-acting bronchodilator inhaler which relaxes the bronchial muscles BUT may also have negative effects on the heart. These drugs increase the heart rate which is already elevated during moderate to vigorous exercise.

Best approaches to exercise for the asthmatic: Understand personal risks

It’s important to identify asthma triggers, which may be different and distinct in certain asthmatics. Some patients with asthma will react adversely to exercising specifically outdoors. For these individuals working out in a gym or home environment may be better.

Sometimes it’s the specific type of exercise that triggers airway inflammation. For example, running forces the person to switch from regular, nasal breathing, which warms and humidifies the air as it passes through nasal passages, making it more soothing, to mouth breathing, which neglects that process entirely. The cold air that enters the bronchial passages during running in this case can instigate an asthma attack.

Some types of exercise may be more forgiving for the patient with asthma. Swimming is an activity that coordinates breathing movements with muscle movements. This allows more efficient delivery of oxygen from the lungs while breathing steadily and deeper instead of faster. It’s no accident that many Olympic swimmers happen to be asthmatics.

One tip is to always be aware of air quality on different days and choose indoor training for days with poor air quality.

The goal for a person with asthma: Be safnd exercise smartSafety in exercise is especially important in asthmatics. Regularity is more beneficial than intensity. So exercising most days of the week will have a better payoff than focusing on how intense the exercise effort is.

Spending five to ten minutes warming up before exercise, can go a long way to help prevent symptoms or an asthma attack. Cooling down after exercise is especially important for someone with asthma, since this is the period when the asthmatic is more likely to develop narrowing of the airways and difficulty breathing. Don’t suddenly stop at the end of an exercise routine.

Some asthmatics have to take daily controller medications while others can get by with rescue medications as needed. For those who are taking controller medications, there is an added advantage to taking the Leukotriene modifiers such as Singulair, since it targets the inflammatory substances that arise during exercise.

Exercise has a big payoff

Ultimately, a regular exercise habit has many benefits. It allows the coordination of the different body systems involved in the production of energy needed to fuel the exercise. This includes the respiratory, cardiac and circulatory system. The energy needed by the muscles in exercise is generated in the presence of oxygen. The value of these systems being asked to work in concert is that, over time, this oxygen is delivered more efficiently improving performance of exercise. More energy is available to the muscles to perform the increased efforts.

Exercise should not be feared. It will not make your asthma worse, since it’s not uniquely associated with increased inflammatory mediators. In fact, engaging in regular exercise, following my recommendations, will allow you to enjoy the same health benefits from exercise that we all need which includes helping with weight loss or weight maintenance, better mood, higher HDL (good cholesterol) and reducing the risk of a number of diseases. Always check in with your healthcare professional before beginning an exercise program.

Also check out: How I Conquered Exercise Induced Asthma

Eli Hendel, M.D.
Meet Our Writer
Eli Hendel, M.D.

Eli Hendel, M.D., is a board-certified internist/pulmonary specialist with board certification in Sleep Medicine. An Assistant Clinical Professor of Medicine at Keck-University of Southern California School of Medicine, and Qualified Medical Examiner for the State of California Department of Industrial Relations, his areas include asthma, COPD, sleep disorders, obstructive sleep apnea, and occupational lung diseases. Favorite hobby? Playing jazz music.