Elite Rowers Different Stress State Of Leptin And Other Hormonal Changes

Objective: The purpose of this study was to compare the influence of different training stress on fasting concentrations of plasma leptin, cortisol, testosterone and testosterone cortisol ratio in elite rowers.Methods: Fourteen National male (N =7) and famale (N =7) rowers underwent a 3-week period of heavy training and a 1-week tapering training. The fasting plasma leptin, cortisol, and testosterone were measured before (PT) and after (HT) the heavy training period and after the following tapering period (TP). Leptin concentrations were measured in duplicate by radioimmunoassay. Mean training time of the 3-week heavy training period and 1-week tapering period was 22.0 h.week-1 and 8.2 h.week-1, respectively. An individual 2,000 m rowing test and lactate anaerobic threshold (LAT) were also measured before HT and after TP to assess training efficacy.Result: In women, the 3-week heavy training induced a significant reduction (p<0.05) in the fasting leptin concentration from 7.73 +2.63 to 4.32 +1.28 ng.ml-1. Fasting plasma leptin was significantly increased in TP (10.69 +4.31 ng.ml-1). The decrease in leptin levels was independent of body mass and fat. Meanwhile, resting cortisol of PT did not significantly alter in HT in spite of a significant increase in TP. The fasting plasma leptin and cortisol in male had the same tendency during the study compared with women, but did not reach statistical significance (P >0.05). No significant change in testosterone and testosterone cortisol ratio was found throughout the whole study period (P >0.05). LAT was significantly improved after the training period in both man and woman, while the 2,000 m rowing ergometer performance time remained relatively constant.Conclusion: These findings suggest: 1. The fasting concentration of plasma leptin may be more sensitive to the rapid and pronounced changes in training stress by comparing with those of cortisol and testosterone and the maximal exercise-induced decrease in leptin after the period of heavily increased training volume was thought to be an early sign of overtraining. It appears that leptin may be a potential indicator in monitoring relative training stress in elite female rowers; 2. Gender comparisons revealed that female rowers had higher circulating leptin concentrations whether pretraining or throughout the training period, and for different training stress the effect on plasma leptin levels is greater in female rowers than in males.