Effects of Football on the Pituitary-Testicular Axis (PTA): Differences between Professional and Non-Professional Soccer Players

Summary

Basal levels of LH, FSH, PRL and T, as well as LH, FSH and PRL relative maximum responses (RMRs = peak values/basal values) to an iv bolus of GnRH (0.1 mg) plus TRH (0.2 mg) were evaluated in 7 professional soccer players (PSP) examined on 3 occasions: after a 30 days rest period and 14—15 h from the end of both a customary training session and a strenuous football match, performed at the end of a 3 months regular training program. In 5 out of the 7 PSP a semen analysis was carried out after each endocrine evaluation. The results were compared with those obtained in 10 non-professional soccer players (NPSP) subjected to a similar study protocol, and with the data from 10 healthy, sedentary men. Basal LH values in the rest period were significantly higher (P < 0.05) in PSP than in control men, whereas LH RMR and sperm motility were significantly lower (P < 0.02) in the former group. No significant differences in basal hormone concentration and in the RMRs to GnRH-TRH were observed between PSP and NPSP. The training session performed by the PSP after 3 months of regular training did not significantly affect the hormonal parameters. In contrast, the football match induced a significant increase in PRL basal levels (P < 0.02 vs. controls) and a significant fall in PRL RMR (P < 0.02 vs. controls). In comparison with NPSP, however, T values and the LH RMR did not show any significant rise. In PSP the LH RMR, the increase in PRL basal levels and the decrease in PRL RMR were significantly lower than in NPSP (P < 0.02, P < 0.05 and P < 0.05, respectively). Neither the training session nor the soccer match did significantly affect the seminal parameters. The possible causes for the differences in the endocrine status between PSP and NPSP are discussed in this paper.

Key words

Soccer players - Physical training - Gonadotropins - Prolactin - Testosterone - Spermatogenesis - Stress