Comparative Analysis of Gas Exchange and Cardiorespiratory System Responses of Swimmers and Skiers to Increasing Normobaric Hypoxia and Physical Load

摘要

Qualification-comparable groups of young men engaged in cyclic kinds of sports were tested using a stepwise increasing load on a bicycle ergometer and 25-min exponentially increasing normobaric hypoxia to a final oxygen concentration of 10%. Skiers, who had the greatest values of maximal oxygen consumption during muscular work, showed relaxed cardiorespiratory reactions and a greater decrease in hemoglobin saturation with oxygen in hypoxia. Swimmers, whose ventilatory function in the course of trainings was restricted, developed preadaptation to hypoxia, with changes in external respiration and gas exchange functions, which allowed better saturation of blood with oxygen in lungs during hypoxia. The joint assessment of the aerobic capacity during physical work and physiological responses to hypoxia showed a direct correlation between the individual maximal oxygen consumption and the rate of decrease in the blood hemoglobin saturation in increasing hypoxia, which may be promising for assessing the functional state of athletes and its correction during training.