There is evidence that the overall prevalence of asthma is increasing in the general population. Asthma is the leading cause of chronic illness and the most common chronic respiratory disorder in children. Given sufficient exercise intensity, exercise can trigger acute exacerbations in virtually all individuals with asthma. Heat loss, water loss, postexertional airway rewarming, and the role of several mediators have been proposed as possible mechanisms responsible for the airway obstruction induced by exercise. Exercise-induced asthma can be easily diagnosed and treated in the majority of patients. Physical training should be part of the asthmatic patient's overall plan of management. When properly treated, asthmatic individuals should be able to participate or compete in the majority of sports.