The response of sexual and stress hormones of male lists during continuous intense competition

The aim of this study was to compare hormonal changes in plasma total testosterone (T), cortisol (C), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (P) in two world-class teams, both consisting of 9 top male pro-cyclists, during a real sports situation (the 1998 Nuelta a Espana, a 3-week multi-stage international cycling competition). Venous blood samples were taken the day before the race (S0), after 1 week (S1), after 2 weeks (S2) and at the end of the race (S3). The S0 T level was significantly lower in the team with more racing days in the previous month. There was a significant basal T decrease (p < 0.05) during the race in comparison with the initial value, in spite of the difference in S0 T level between teams. However, there was no difference between teams in the mean decrease in T level. C decreased significantly between S0 and S1 and between S1 and S2, but not between S2 and S3. There were no differences in P concentration between teams or throughout the study, except for a significant increase between S2 and S3. There were no initial differences in LH nor FSH concentration between the teams, nor at any of the study follow-up times. We conclude that in professional top-level athletes S0 T values depend on the number of competition days of the previous month. We observed a similar decrease in the T levels in both teams, independent of the absolute S0 values. In both teams C decreased during long-lasting cycling competition.