What is exercise-induced asthma?
Exercise can be a trigger for asthma symptoms for some people, known as exercise-induced asthma.
Vigorous exercise makes people breathe quicker, which affects airflow, and the moisture content and temperature of the air.
Understanding the circumstances that trigger exercise-induced asthma can help a person have a healthy workout, without making their asthma symptoms worse.
Asthma is not a barrier to sports performance. A quarter of the Team GB athletics squad for London 2012 had asthma.
Why does exercise induce asthma?
During normal breathing, the air we breathe is first warmed and moistened by the nasal passages. Because people tend to breathe through their mouths when they exercise, they are inhaling colder and drier air.
In exercise-induced asthma, the muscle bands around the airways are sensitive to these changes in temperature and humidity and react by contracting, which narrows the airway.
This results in symptoms of exercised-induced asthma, which include:
- Coughing with asthma.
- Tightening of the chest.
- Unusual fatigue while exercising.
- Shortness of breath when exercising.
The symptoms of exercise-induced asthma generally begin within 5-20 minutes after the start of exercise, or 5-10 minutes after brief exercise has stopped. If you are experiencing any of these symptoms with exercise, seek medical advice.
If I have asthma, should I avoid exercise?
No. You shouldn't avoid physical activity because of exercise-induced asthma, unless medically advised to do so. There are steps you can take to prevent asthma symptoms that will allow you to maintain normal physical activity. The following is a list of some sports people with asthma:
- Paul Scholes - footballer.
- Paula Radcliffe - marathon runner,
- Ian Botham - cricketer.
- Gethin Jenkins - rugby player.
- Dennis Rodman - American basketball player.
- Jackie Joyner-Kersee - American heptathlete.
Can my exercise-induced asthma be prevented?
Yes. Asthma inhalers used prior to exercise can control and prevent exercise-induced asthma symptoms. The preferred asthma medications are short-acting beta-2 agonists such as salbutamol. Taken 15-20 minutes before exercise, these medications can prevent the airways from contracting and control exercise-induced asthma for as long as four to six hours.
In addition to taking medication, warming up prior to exercising and cooling down after exercise can help in asthma prevention. For those with allergies and asthma, exercise should be limited during high pollen days or when temperatures are extremely low or air pollution levels are high. Infections (colds, flu, sinusitis) can exacerbate asthma and increase asthma symptoms, so it's best to restrict your exercise when you're unwell.