Asthma is a long-term (chronic) condition causing swelling and narrowing of the airways. The muscles around the airways tighten, the lining of the airways swells, and extra mucus is produced. These changes make it harder to breathe. Triggers are things that cause asthma flare-ups and make symptoms worse. Triggers may be dust, pollen, pets, infections, cold weather, smoke, air pollution, and exercise.
Exercise is a common trigger for many people with asthma. For some people, exercise, along with other things, causes asthma symptoms. For others, asthma symptoms happen only with exercise or physical activity. In both cases, this is called exercise-induced bronchoconstriction (EIB). (It used to be called exercise-induced asthma.) This means that exercise causes the airways (bronchi) to narrow or constrict.
Living with EIB doesn't mean you need to give up exercise. Exercise is important for overall good health. It also helps keep the lungs and muscles used for breathing strong. Your body needs exercise. Work with your health care provider to develop an exercise program that allows you to exercise safely with as few symptoms as possible.