arginine does not increase HGH.[Effect ofsupplementation on secretion of human growth hormone and insulin-like growth factor in adults].
[Article in Portuguese]
Fayh AP, Friedman R, Sapata KB, Oliveira AR.
Laboratório de Pesquisa do Exercício, Escola de Educação Física, Universidade Federal do Rio Grande do Sul, Rua Felizardo 750, 90690-200 Porto Alegre, RS. firstname.lastname@example.org
Based on presumptions that the of amino acids can augment the release of human growth hormone (hGH) and that this metabolism is related with secretion of insulin-like growth factor I (IGF-I), the purpose of this study was to verify the effect of supplementation on GH and IGF-I in adults. Seventeen male individuals participated on the study and were randomized to receive L-arginine (n= 10) or placebo (n= 7), seven grams per day for seven days. Before and after the supplementation period, the volunteers realized blood collection in fasting to verify both GH and IGF-I levels, as well as urine collection to verify urea excretion. At the end of the experimental period, it was verified that the group that received L-arginine augmented the urea in urine excretion (to 2684.1 +/- 475.2 mg/dl from 2967.2 +/- 409.7 mg/dl, p= 0.002), therefore it did not alter significantly the release of hormones evaluated. The group which received placebo did not alter significantly any evaluated parameters. The L-arginine supplementation during seven days was ineffective to augment both GH and IGF-I release in individual male adults.