Adrenocorticotropic hormone, beta-endorphin, cortisol, growth hormone and prolactin circulating levels in nineteen athletes before and after half-marathon and marathon.

Circulatory levels of ACTH, beta-endorphin (beta-Ep), prolactin (PRL), growth hormone (GH) and cortisol were evaluated in 19 volunteers athletes 48 h, 1 h before and soon after an international marathon (Romaratona 1988) and a national half-marathon. ACTH, beta-Ep and cortisol levels 48 h and 1 h before the half-marathon were similar, whereas 1 h before the marathon they were significantly elevated (p less than 0.01). Presumably the stress produced by the expectancy of the race induce a significant increase of the hormones of the hypothalamus-pituitary-adrenal axis in the very competitive marathon (Romaratona 1988). Moreover a remarkable increase of ACTH, beta-Ep, GH, PRL and cortisol circulating levels has been observed in the athletes after both runs, but in a different extend in relation not only to the duration and intensity of the muscular work but also to the agonistic effort: thus the hormonal increase was higher after the international marathon run than after the national half-marathon.