Reactivity of cardiorespiratory system and manifestations of fast kinetics responses in athletes of different sports specialization

Abstract

The purpose of the study was to determine differences in the fast kinetics of O2 consumption, CO2 release, pulmonary ventilation and heart rate, as well as differences in sensitivity of the cardiorespiratory system (CVS) to hypercapnia in athletes of various sports specializations. Methods. In three groups of elite runners (19–24 years old) at a distance of 100, 800 and 5000 m peak responses and their fast kinetics were studied (half cycle T50, «breath-by-breath» method). Sensitivity to CVS hypercapnia was determined by the «return» breathing method. Results. It was revealed that the fast kinetics of •VO2 and •VE, when performing work of average aerobic power at •VO2 53.5 % of •VO2max was higher in sprinters as compared to long-distance runners. For «critical» power at •VO2 93,4 % of •VO2max the characteristics of reaction kinetics were higher in long-distance runners. The findings suggest an association between differences in CVS sensitivity to CO2 in sprinters, middle and long distance runners, and differences in the kinetics of fast reactions of CVS in athletes. The value of ΔРАСО2/ΔVE was significantly higher for sprinters as compared to long and middle distance runners. Conclusions. The findings indicate the differences in CVS sensitivity to CO2 in sprinters, middle and long distance runners, as well as differences in the kinetics of fast reactions of CVS in athletes, differences in the degree of involvement of anaerobic metabolism and VCO2 kinetics. The latter has been associated with respiratory compensation of metabolic acidosis, which provided the most pronounced differences between long and middle distance runners, as well as sprinters.