Endorphin responses to stress induced by competitive swimming event.

Aim: The aim of the present study was to investigate the changes in endorphins (END) induced by swimming competitive practice.

Methods: Twenty-three males, (13 trained swimmers [experimental group] and 10 sedentary and healthy students [age-matched comparison group]) took part in this investigation. The swimmers were assessed at 3 points: basal conditions, pre- and postswimming competition (100 m freestyle), whereas subjects from the control group only undertook the basal trial.

Plasma concentrations of beta-endorphin and adrenocorticotropic hormone in women with and without childbirth preparation.

We studied plasma concentrations of beta-endorphin (beta-EP) and adrenocorticotropic hormone (ACTH) during dilation, expulsion and immediate puerperium in 47 primiparous women with an uneventful pregnancy and spontaneous vaginal delivery. Twenty-five women had received childbirth preparation with the Lamaze method, and 22 had received no preparation. Mean concentrations of beta-EP from the beginning of labor until puerperium were higher in women who had received preparation, but there was no significant difference between the two groups.

Plasma levels of beta-endorphin and ACTH during labor and immediate puerperium.

We measured concentrations of beta-endorphin (beta-EP) and adrenocorticotropic hormone (ACTH) in maternal peripheral plasma during dilation, the expulsive period and immediate puerperium, and in the umbilical vein. Plasma levels of both peptides increased markedly and were directly correlated during labor, and decreased 24 h after birth; they were no longer correlated during immediate puerperium. In the umbilical vein, beta-EP and ACTH were also directly correlated.

Beta-endorphin and ACTH in plasma: effects of physical and psychological stress.

The effects of the expectancy of an official race (22000 m) and the performance of this last event on plasma levels of beta-Endorphin (B-End) and ACTH have been assessed. In a group of nine athletes, samples were obtained first in basal conditions; second in the day of the run before the warming up period and third after running. B-End immunoactivity was increased from 15.