Influence of resistance training in left ventricle of ovariectomized elderly rats

Abstract

Several cardiovascular changes evoked by aging affect negatively the quality of people's lives, among them is the reduced functional capacity. Menopausal women, affected by the suspension of the ovarian hormones, suffer more intensely from metabolic and cardiovascular changes. It is known that physical training causes biochemical, electrical, morphological, and mechanical adaptations in the cardiac muscle, which together provide an improvement in the cardiac function. The goal of the present study was to evaluate the effect of resistance training in the left ventricle of ovariectomized rats through stereological analysis. We studied 15 Wistar female rats, 4 months- old, average weight 240 g. All animals were ovariectomized at 9 months of age and then divided into 3 groups of five individuals as follows: Ovariectomized Sedentary Adult (13 months) (OSA), Ovariectomized Sedentary Elderly (17 months) (OSE), and Ovariectomized Trained Elderly (17 months) (OTE). The rats were monitored for 13 months and subsequently underwent resistance training for 12 weeks. The stereological analysis was performed using light microscopy techniques and data obtained for each group were tabulated and statistically compared using ANOVA and post hoc Tukey tests (p ≤ 0.05). It was verified that training decreased volume density of myocyte, interstitium and collagen fibers followed by increased volume density of capillaries, when compared with the ovariectomized sedentary elderly (OSE). Our data suggest that resistance training minimizes changes in the myocardium of elderly rats deprived of ovarian hormones.