EXERCISE AND ASTHMA
'He runs about all right for five minutes or so, but when he stops his chest
immediately tightens up so that within a short while he can hardly breathe at
all.'
A mother describes how her child's asthma is brought on (triggered) by
exercise.
Why exercise may start an asthma attack
People with asthma have airways that are almost always red and sore
(inflamed). Because they are inflamed the airways are quick to respond to
anything that irritates (triggers) them. Although they vary from person to
person, triggers such as flu, cigarette smoke and cold air can make the airways
narrower by tightening the surrounding muscles. Exercise is also a common
trigger and when the symptoms of asthma (coughing, wheezing, chest tightness or
breathlessness) follow exercise this is either called exercise-induced asthma
or exercise asthma.
Exercise-induced asthma does not mean the end of exercising. It can often be
effectively treated so that people with asthma can choose to take almost any
sort of exercise: many Olympic medals have been won by people with asthma.
Exercise is good for everyone; so this booklet sets out to explain what is
known about exercise-induced asthma and how it is best prevented or treated.
How to recognise exercise-induced asthma
It may be difficult to tell the difference between normal breathlessness
after exertion and asthma caused by exercise. We all get 'puffed out' by
vigorous exercise. However, if someone is wheezing, coughing or their chest
tightens they should ask their doctor if it is caused by asthma. The symptoms
may be most obvious within a minute of stopping exercise, get worse over a few
minutes and last for up to half an hour.
Both adult and child asthma can be triggered by exercise: sometimes even
when it is otherwise well controlled. Some people's symptoms after exercise are
the only sign of asthma since they do not cough or wheeze at any other time.
There are times when exercise-induced asthma is more likely to develop
because the airways are more irritable, such as after a cold or during the
pollen season. At these times even short, mild activities may trigger an
attack. On cold, dry days the chances of wheezing with exercise also go up.
The causes of exercise-induced asthma
One important cause seems to be the temperature and the moisture content of
the air. Indoor swimming, for instance, does not appear to cause asthma as
often as running and other forms of outdoor exercise. The indoor pools are warm
and moist; in contrast, on a frosty winter day the air outside is cold and dry.
Therefore, breathing large amounts of cool or dry air can trigger
exercise-induced asthma; whereas warm, moist air is less likely to cause
problems.
Why spotting exercise-induced wheezing is important
- It may be the first clue to a diagnosis of asthma.
- Asthma medicines can then help the person to exercise more freely.
- Wheezing in adults may suggest poor asthma control, so the person may need
more medication.
How doctors spot exercise-induced asthma
Often the knowledge that symptoms appear after exercise is all that a doctor
needs to diagnose exercise-induced asthma. He or she may confirm it by seeing
if a peak flow measurement of the lungs (breathing test) drops after six
minutes of exercise. If it does the diagnosis is probably correct; the doctor
may then suggest a couple of puffs of a reliever inhaler and check the peak
flow reading again after a few minutes.
Conquering exercise-induced asthma
The best approach is to prevent the symptoms by taking medicine before
exercising: only cut back on exercise or the type of exercise if absolutely
necessary.
Preventing the symptoms
Several 30-second sprints over five to ten minutes before vigorous games may
protect the lungs for an hour or so.
Taking medication a few minutes before exercising can reduce symptoms. The
doctor may advise either:
- Two puffs from a reliever inhaler before exercising. (Normally the reliever
inhaler is only used when asthma symptoms appear.)
- Sodium cromoglycate (Intal, Cromogen) may prevent exercise-induced asthma
if it is taken just before exercising. It will not relieve exercise-induced
wheezing once it has started.
If these medicines do not prevent the coughing and wheezing, then the
reliever inhaler may be used again.
Theophyllines (such as Phyllocontin or Slo-Phylin) and inhaled steroids
(such as Pulmicort, Becotide, Becloforte or Flixotide) do not prevent
exercise-induced asthma. Although regular treatment with sodium cromoglycate
(Intal, Cromogen) or the inhaled steroids can often reduce the symptoms
generally, these medicines (known as preventers) do not relieve symptoms once
they have appeared.
Safety of medicines in sport
The inhaled steroids used to treat asthma are called corticosteroids. They
are not the same as anabolic steroids which some athletes use to improve their
performance. The sporting regulatory agencies allow most inhaled asthma
medicines to be taken. For more information please contact the Doping Control
Unit at the Sports Council on 071 383 5667.
What to do if the medicines are not helping
If the medicines do not help sufficiently well it is worth remembering the
following:
- Wheezing is usually worse on cold, dry days.
- Long spells of exercise are more likely to induce asthma than short bursts.
- Exercise with arms or legs alone is less likely to trigger an attack than
exercise using both.
So cross-country running on a cold winter's day might not be a good idea but
sprinting and jumping in the summer may be fine. Common sense decisions, such
as playing a less active position in team games, can make all the difference
between taking part and not playing at all.
For more information about asthma in general please see the 'Take control of
asthma' booklet, produced by the National
Asthma Campaign or call the Asthma Helpline on 0345 010203.
|
