British well known national daily newspaper the Guardian wrotes last week: "The idea of a supremely fit professional cyclist like Simon Yates having to occasionally reach for an inhaler to ward off a wheeze might seem anomalous. But asthma is surprisingly common among some elite athletes.
A handful have classic asthma, the usually allergy-triggered constriction of the bronchial tubes that tends to begin in childhood.
Much more common in sport is exercise-induced asthma, or EIA, in which rapid and heavy breathing causes the same symptoms. The effect can be exacerbated by atmospheric conditions, which means some sportspeople tend to suffer more than others.
John Dickinson from Kent University’s school of sport & exercise sciences, a world expert on asthma in sport, tested all 33 UK-based members of the British swimming squad and found 70% had some form of asthma, against a national asthma rate of about 8% to 10%. It is believed the chlorinated atmosphere of a pool could be a factor in this."
Read our article on Exercise-Induced Bronchoconstriction in Athletes (full text article from Austin Journal of Pulmonary & Respiratory Medicine):