Acute effects of different intensities and amounts of aerobic exercise on the concentrations of tryptophan and serotonin in physically active elderly women

Abstract

Aging causes a decrease in the concentration of serotonin, which in turn, can produce abnormalities of behavior as aggression, insomnia, suicidal or criminal behavior and loss of sexual desire. However, studies show that aerobic exercise seems to increase acutely the concentrations of tryptophan and serotonin. Furthermore, there are no reports of studies that have investigated the effects of different intensities and volumes of aerobic exercise on the concentrations of tryptophan and serotonin in older women physically active. The aim of this study was to determine the acute effects of different intensities and volumes of aerobic exercise on the levels of tryptophan and serotonin in older women. For this, 49 older women (aged 60 to 75 years) physically active were divided into six groups: being a control group (CG, n = 8) and five experimental groups: 1) aerobic exercise performed at 90% of ventilatory threshold (VT90, n = 8); 2) intensity exercise performed at ventilatory threshold (VT, n = 8); 3) intensity exercise performed on 90% of the respiratory compensation point (RCP90, n = 8), each with lasting 20 min; 4) maximal incremental test (MIT, n = 8); and 5) exercise held in ventilatory threshold intensity with lasting 60 min (VT60min, n = 9). Before and after completion of the exercise sessions, venous blood samples were collected to quantify the levels of tryptophan and serotonin. There were no differences (p >; 0.05) between and within groups in the concentrations of serotonin and tryptophan. In conclusion, acute bouts of aerobic exercise performed at different intensities and volumes did not result in significant changes in the concentrations of serotonin and tryptophan in older women.