Hormonal responses to training and its tapering off in competitive swimmers: relationships with performance.
During a winter training season, the effects of 12 weeks of intense training and 4 weeks of tapering off (taper) on plasma hormone concentrations and competition performance were investigated in a group of highly trained swimmers (n = 8). Blood samples were collected and the swimmers performed their speciality in competition at weeks 10 (mid-season), 22 (pre-taper) and 26 (post-taper). No statistically significant changes were observed in the concentrations of total testosterone (TT), non-sex hormone binding globulin-bound-testosterone (NSBT), cortisol (C), luteinising hormone, thyroid stimulating hormone, triiodothyronine, thyroxine plasma catecholamines, creatine kinase and ammonia during training and taper. Mid-season NSBT: C ratio and the amount of training were statistically related (r = 0.82, P < 0.05). Competition performance slightly declined during intense training [0.52 (SD 2.51)%, NS] and improved during taper [2.32 (SD 1.69)%, P < 0.01]. Changes in performance during training and taper correlated with changes in ratios TT: C (r = 0.86, P < 0.01 and r = 0.81, P < 0.05, respectively) and NSBT: C (r = 0.77, P < 0.05 and r = 0.76, P < 0.05, respectively). In summary, these results showed that the monitored plasma hormones and metabolic indices were unaltered by 12 weeks of intense training and 4 weeks of taper. The TT: C and NSBT: C ratios, however, appeared to be effective markers of the swimmers' performance capacities throughout the training season.
Mujika
I
I
Laboratoire de Physiologie-GIP Exercise, Faculté de Médecine, Université Jean Monnet, Saint-Etienne, France.
Chatard
J C
JC
Padilla
S
S
Guezennec
C Y
CY
Geyssant
A
A
D000328:Adult; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D013550:Swimming; D013739:Testosterone / Q000378:metabolism*
D013739:Testosterone; D006854:Hydrocortisone