RESEARCH Association of serum Clara e

Full list of author information is available at the end of the articleBackground Strenuous exercise characteristic of endurance sports is believed to have a detrimental effect on the integrity of the structure of the respiratory epithelium. Such damage may lead to increased bronchial hyperresponsiveness to non-specific stimuli and contribute to the increased prevalence of exercise-induced bronchoconsriction ob-served in elite endurance athletes [1-4]. Endurance sports may be also associated with increased susceptibility to respiratory infections [5], which in turn, may exert a de-structive effect on the airway epithelium. Various proteins have been assessed as potentially use-ful tools in monitoring airway inflammation and epithe-lial damage [6-9]. Clara cell secretory protein (CC16), a protein secreted by non-ciliated cells of the bronchioles, * Correspondence