In the last ten years, the effects of exercise on bronchial epithelial cells and inflammatorycells in the airways have been studied in detail, and such new information has beencombined with previous knowledge on bronchial reactivity and asthma evoked by exercisein asthmatic patients and athletes. The resulting picture is very complex, and the potentialclinical consequences are often contradictory, suggesting the opportunity to define differentphenotypes of exercise-associated airway changes (Lee & Anderson, 1985; Haahtela et al.,2008; Moreira et al., 2011a).Studies in asthmatic athletes in the 90’ had began to explore the possibility that airwayinflammation might be involved in exercise-associated respiratory symptoms. However,studies in non-asthmatic athletes also found increased number of inflammatory cells notonly at rest, but also after strenuous endurance exercise (Bonsignore et al., 2001). It wastherefore hypothesized that endurance exercise may physiologically cause influx ofinflammatory cells into the airways, associated with low or absent inflammatory activation(Bonsignore et al., 2003a). Subsequent studies in athletes and animal models have extendedthese finding, but the mechanisms of inflammatory cell recruitment into the airways and thetight control of inflammatory activation physiologically associated with exercise remainpoorly understood.Exercise is a known cause of bronchoconstriction in asthmatic patients (Cabral et al., 1999)and athletes (Parsons & Mastronarde, 2005). A large number of asthmatic elite athletesparticipate to international top-level competitions, and guidelines regarding management ofasthmatic athletes (Fitch et al., 2008) and rules on the use of anti-asthmatic drugs have beenissued (World Anti-Doping Agency, WADA, Oct. 18 2010 report). However, exercise is apowerful physiologic stimulus for bronchodilatation, and some reports underlined thatexercise training may actually downmodulate bronchial reactivity in normal subjects(Scichilone et al., 2005, 2010), asthmatic children (Bonsignore et al., 2008) and animal modelsof asthma (Hewitt et al., 2010).This chapter will summarize the changes induced by acute exercise and training inbronchial reactivity and airway cells in both humans and animal models. It will also discussthe changing paradigm regarding the impact of physical activity in patients with bronchialasthma, and the new perspectives of exercise-based rehabilitation in patients withrespiratory diseases such as chronic obstructive pulmonary disease (COPD).
|Title of host publication||An International Perspective on Topics in Sports Medicine and Sports Injury|
|Number of pages||26|
|Publication status||Published - 2012|
- Physiology (medical)