Sugar Land - Visiting Nurse Assn. Most people diagnosed with asthma will experience asthma symptoms when exercising. In addition, about 11 percent of the US population who are not diagnosed with asthma will experience asthma symptoms, but only during exercise, a condition called exercise-induced asthma.
Some people have both types of asthma, while others only experience exercise-induced asthma.
Unfortunately, the basic cause of asthma is still not known. When breathing normally, the air that enters the airways is first warmed and moistened by the nasal passages to prevent injury to the delicate lining of the airways. When asthma symptoms begin, the airways' muscles constrict and narrow, the lining of the airways begins to swell, and mucus production may increase. In addition, when breathing through the mouth during exercise, a person will inhale more air-borne particles, including pollen, which can trigger asthma. Exercise-induced asthma is characterized by asthma symptoms such as coughing, wheezing, and tightness in the chest within five to 20 minutes after starting to exercise.