www.pneumonologia.viamedica.pl EDITORIAL 379 Correspondence address: Correspondence address: Correspondence address: Correspondence address: Correspondence address: Monika Franczuk, MD, PhD, Lung Function Department, Institute of Tuberculosis and Lung Diseases in Warsaw, Plocka 26 St., 01–138 Warszawa, e-mail: m.franczuk@igichp.edu.pl Date of paper receipt at the editorial office: 14 Sept 2011. Copyright © 2011 Via Medica ISSN 0867-7077 Monika Franczuk Lung Function Department, Institute of Tuberculosis and Lung Diseases in Warsaw Head: Prof. S. Wesolowski, MD, PhD Recognition of exercise-induced bronchoconstriction — a task for a medal Rozpoznawanie powysilkowego skurczu oskrzeli — zadanie na medal Pneumonol. Alergol. Pol. 2011; 79, 6: 379-381 A physiological response to exercise leads to increased ventilation, which is an adaptive mecha- nism related to increased body demand for oxygen and accelerated metabolism. Maintaining constant blood gasometry parameters is the main task of the breathing control system. Increased respiratory drive and intensified activity of respiratory musc- les lead to increased tidal volume. During strenu- ous physical exercise, when this volume reaches the level of approximately 70-75% of total lung capacity, breathing frequency is also significantly higher. In poorly trained individuals, intense bre- athing may be interpreted as a pathological symp- tom, dyspnoea, especially if it impairs normal func- tioning and causes respiratory discomfort and con- siderable fatigue. On the other hand, diseases of the respiratory system such as chronic obstructi- ve pulmonary disease or pulmonary fibrosis are accompanied by impaired exercise tolerance, re- sulting in the need to reduce the intensity of ef- fort. These are immanent features of disease pro- gression and impaired lung function. A specific clinical situation is the occurrence of dyspnoea and respiratory symptoms during or after strenuous physical exercise. Exercise-indu- ced bronchoconstriction (EIB) is a term for tran- sient constriction of the airways leading to impa- ired air flow and symptoms such as cough, whe- ezing, or dyspnoea, which appear during strenu- ous physical exercise or, more frequently, after its discontinuation. A delayed reaction, which occurs less often, refers to a bronchospasm that appears 3 to 8 hours after exercise. The pathogenesis of this phenomenon is not fully understood. Intense exer- tion and increased ventilation cause water loss and increased osmolarity of airway mucus [1]. Thro- ugh the activation of mast cells, epithelial cells, eosinophils, stimulation of nervous endings, and release of numerous inflammatory mediators, histamine, prostaglandins, or leukotrienes it results in constriction of bronchial smooth muscle, mu- cosal oedema, and increased vascular permeabili- ty. According to another theory, called thermic or vascular, the main role is played by exposure to cool air, which contributes to vasoconstriction pre- venting heat loss. Discontinuation of exercise and reduction of ventilation cause vasodilation, con- gestion, and mucosal oedema, resulting in narro- wing of the bronchi and restricted air flow. It se- ems that exercise-induced bronchoconstriction is a result of both mechanisms. Exercise-induced bronchoconstriction may occur in patients with diagnosed asthma; up to 90% of patients report exercise-induced symptoms [2]. It usually indicates insufficient disease control and the necessity of treatment modification. Exer- cise-induced bronchoconstriction also affects 10- 15% of the general population, including indivi- duals without a history of asthma or atopy. EIB is significantly more frequent in sportsmen, especial-