In athletes, symptoms of bronchospasm such as chest discomfort, breathlessness, and fatigue are often falsely attributed to the individual being out of shape, having asthma, or possessing a hyperreactive airway rather than EIB.

[4] Mouth breathing as a result of decreased nasal breathing also increases lung surface exposure to irritants, pollutants, and allergens, causing neutrophilic inflammation in response to reactive oxygen species formation; research has found that individuals with genetically hindered glutathione counteraction of this oxidative stress are likely at a higher risk of developing EIB.

[5] Exercise-induced bronchoconstriction can be difficult to diagnose clinically given the lack of specific symptoms[2] and frequent misinterpretation as manifestations of vigorous exercise.

It is also important to distinguish those who have asthma with exercise worsening, and who consequently will have abnormal testing at rest, from true exercise-induced bronchoconstriction, where there will be normal baseline results.

[9] Treadmill or ergometer-based testing in lung function laboratories are effective methods for diagnosing exercise-induced bronchoconstriction, but may result in false negatives if the exercise stimulus is not intense enough.

The presence of the enriched CO2 compensates for the CO2 losses in the expired air, not matched by metabolic production, that occurs during hyperventilation, and so maintains CO2 levels at normal.

[18] Some physicians prescribe inhaled anti-inflammatory mists such as corticosteroids or leukotriene antagonists, and mast cell stabilizers have also proven effective.

[20] A crossover study compared oral montelukast with inhaled salmeterol, both given two hours before exercise, showing that the drugs had similar benefit.

[23] Other athletes with EIB include racing cyclist Simon Yates, distance runner Paula Radcliffe[24] and cross-country skier Marit Bjørgen.

[25] Research by sports scientist John Dickinson found that 70 percent of UK-based members of the British swimming team had some form of asthma, as did a third of Team Sky cyclists, compared to a national asthma rate of eight to ten percent,[24] whilst a study by the United States Olympic Committee in 2000 found that half of cross-country skiers had EIB.