Strenuous activity can trigger an asthmatic response. This response occurs when rapid deep breaths during exercise cause the airways to become cool and dry. Vigorous exercise is more likely than mild or moderate exercise to cause exercise-induced asthma.

Exercise-induced asthma attacks are usually brief and may occur during or after exercise. Symptoms generally begin after six to 12 minutes of exercise, and reach their worst within 10 minutes after exercise has stopped.

In fact, regular moderate exercise is a good thing for people with asthma. Note, however, that some exercise environments are better than others. Activities in warm, humid air, such as an indoor swimming pool, are best, as long as you are not allergic to mold. Exercising in cold, dry air is more likely to trigger an attack. If you exercise outdoors in cold weather, you should wear a scarf or a cold-air mask, which you can buy in a drugstore.

Breathing through your nose can help because your nasal passageways humidify and warm the air before it enters your lungs. Exercise-induced asthma is aggravated by strenuous activities that cause rapid breathing through the mouth. It may be helpful for to do warm-up exercises before your workout.

Using a puff of a bronchodilator medication about 20 minutes before you exercise is a good way to prevent bronchospasm during exercise. Medications used for this purpose include albuterol (Ventolin and Proventil). Other medicines that can prevent a reaction to exercise for some people include cromolyn sodium (Intal) and nedocromil (Tilade). These medicines, unlike albuterol, work only for prevention and do not relieve attacks once asthma has appeared.

Some individuals who have wheezing with exercise do not actually have asthma, they have a separate breathing problem relating to spasm of the vocal cords. If you do not have improved symptoms when you use a bronchodilator medicine before you exercise, your doctor and you may reconsider your asthma diagnosis.