Effect of Intensive Physical Loads on Plasma Testosterone and Cortisol Concentration in Elite Athletes

Abstract

The study purpose was to investigate changes in the content of testosterone and cortisol in the blood of qualified athletes after testing them to determine their maximal oxygen consumption (VO2max). 
 Materials and methods. Thirty-seven international level athletes: 15 biathletes, 12 rowers, 6 boxers, 4 modern pentathletes participated in this study. The test to evaluate VO2max used exercise of increasing intensity on a rowing ergometer for rowers and on a treadmill for biathletes, boxers, modern pentathletes. Total testosterone and cortisol concentrations were determined in blood serum by an immunoenzyme analyzer before and after the test for determination of VO2max. 
 Results. The concentration of total testosterone has been found to decrease significantly on average by 24,4% and the concentration of cortisol has increased by 34% due to physical activity. The highest level of maximum oxygen consumption was found in athletes with high levels of basal testosterone and cortisol in the blood. There is a high correlation between the basal content of total testosterone and the maximum consumption of oxygen in athletes (r = 0,58). 
 Conclusions. The high content of basal testosterone and cortisol is an important factor for the athlete’s special working efficiency: higher level of basal cortisol has been accompanied by smaller increases in cortisol per load and high basal level of testosterone makes is possible to keep its concentration sufficient. The concentration of total testosterone and cortisol can be used as a marker of the effect of a training load.