Pulmonary function parameters changes at different altitudes in healthy athletes

ABSTRACT

Hypoxia and hypocapnia can cause broncho-constriction in human subjects, and this could have a bearing on performance at high altitude. The object of this study was to examine how pulmonary ventilatory functions during high-altitude trekking. This study is a cohort study on spirometric parameters at different altitudes. Fifty six healthy male volunteers from a university student population were enrolled in the study [ages 22.9 +/- 5.3 years]. Pulmonary function was assessed with a Spirolab II in all participants before ascending at baseline [1150 meter], after ascending at different altitudes [2850, 4150 meter], and after descending at sea level during a 3-day trek in Sialan Mount. This study indicates that in an actual trek, ascending results in significant decrease in forced vital capacity [FVC]. FVC significantly decreased with increasing altitude from baseline level and at the sea level it was significantly less than baseline level. Peak flow increased with increasing altitude from baseline [1150 m] to 2850 m and decreased with decreasing altitude [p < 0.01]. Maximal midexpiratory flow rate [FEF 25-75%] and forced expiratory volume in 1 second to forced expiratory volume ratio [FEV1.0%] significantly increased with increasing and decreasing altitude from baseline level [p < 0.001]. There was no significant change in FEV1. It could be concluded that changes in some pulmonary ventilatory parameters were proportional to the magnitude of change in altitude during a high-altitude trek. These changes are significant at the beginning of ascending