Abstract

Changes in blood levels of cortisol, growth hormone (GH) and progesterone were recorded in crew members of the eight-oar boat during a mesocycle of high intensity training in the middle of the competition period. An interval exercise (7 bouts, 40 s each, of rowing at the highest possible rate, separated by 20 s-intermissions), as well as competitions (2000 m race) and its model (7 min rowing on a rowing ergometer) caused significant rises in cortisol and GH concentrations. The first two microcycles were followed by some suppression of adrenocortical activity and the pituitary GH function, reflected in lowered cortisol levels before training sessions and after interval exercise, as well as in reduced GH response. Progesterone cortisol ratio (PCR) decreased in response to exercise, but the above-mentioned inhibition of adrenocortical function had no effect on that ratio. The competition race resulted in highest increase of cortisol, GH and PCR. In the microcycle following competition high cortisol response to the 7 min-rowing test coincided with low values of PCR, sugesting a transient but marked exhaustion of the potential for steroid hormone synthesis. In the following microcycle, cortisol levels and PCR returned to normal values. Verf.-Referat