Differential impact of endurance, strength, or combined training on quality of life and plasma serotonin in healthy older women

Aging is associated with a progressive decline in physical and neurophysiological functions, and some studies suggest that cerebral serotonin is decreased in older adults. These factors contribute to reduced ability to perform daily activities, influencing quality of life (QoL). Regular physical activity has demonstrated important benefits in reversing ageing effects; however, little is known whether different training protocols might induce differential effects on QoL. The aim of this study was to verify the effects of different types of training on QoL and its relation with plasma serotonin in healthy older women. Forty-eight older women were randomly assigned in four groups: Strength Training (ST), Endurance Training (ET), Combined Training (CT), and Control Group (CG) which was instructed not to engage in any physical exercise during the study time. Participants underwent 12 weeks of training twice a week. Plasma serotonin and a scoring system questionnaire SF-36 for evaluation of QoL were assessed at baseline and after the completion of training protocols. When comparing pre- and post-training periods all trained groups showed improvement in QoL, but the CT improved more domains. Plasma serotonin was significantly lower in the ST and in the CT groups in comparison with controls after the 12-week training. Significant correlations of plasma serotonin with physical functioning, role-physical, general health, vitality, and mental health were observed. CT resulted in higher amelioration in QoL, in comparison with ET or ST only. All training protocols induced significant reductions in peripheral serotonin levels, which were negatively correlated with improvements in QoL.