DOCTOR ON CALL/ASK THE EXPERT:I PLAY Gaelic football at under-16 club level. My doctor diagnosed mild asthma recently and gave me an inhaler to take when I get symptoms. Another girl on the team takes her inhaler before every match and training sessions even when she is not wheezy. Should I do the same?
EXERCISE IS a well-known trigger for asthma. Vigorous exercise causes a temporary narrowing of the main airways in the lungs. Some 80 to 90 per cent of people with asthma experience exercise-induced bronchospasm.
People without asthma may also experience temporary airway narrowing, usually when they have a chest infection or if they are exposed to very cold air.
But for people like yourself with established asthma, it seems the airways are much more sensitive to exercise. The exact reason for this is unclear: it may be related to air pollution; hyperventilation may dry up the breathing tubes especially in cold dry air; and exercise itself may stimulate the release of the chemicals directly responsible for narrowing the airways in the lungs.
Up to one in five elite athletes experience exercise-induced asthma, so when managed properly it is clearly not a barrier to sporting success.
Just think of the blistering pace of Denis Hickie in an Irish rugby jersey - the recently retired winger has had asthma for most of his life.
It sounds like you have not noticed any obvious symptoms such as wheeze, cough or shortness of breath when you exercise.
Sometimes, though, the signs can be more subtle. Have you experienced tummy pains after exercise? Do you feel "out of shape" after exercising or is it more difficult for you to train in cold air?
Another clue is when you have no difficulty exercising in an indoor swimming pool, but notice a cough or chest discomfort when running outdoors. (Moist warm air blocks airway narrowing).
One of the good things about exercise-induced asthma is that after the initial tightening of the airways, almost 50 per cent of those who experience the problem enter a refractory phase of up to three hours, during which no further narrowing occurs.
So for some athletes, "running through" their asthma allows them take advantage of this. Others find that a short burst of activity gets them into the protected phase.
No matter what degree of asthma you have, it is a good idea to warm-up before training for 10 to 15 minutes and to cool-down after for about 10 minutes. A warm shower after the session may also help open up the airways.
As for your inhaler, please check with your doctor for his specific advice. However, I expect he will tell you to take the "reliever" inhaler 15-20 minutes before training.
Doing this prevents exercise- induced airway constriction in almost 95 per cent of people with asthma.
Dr Muiris Houston is Medical Correspondent of The Irish Times. Email queries to sportsdoctor@irish-times.ie
