Effects of resistance exercise on ascendent aorta on ovariectomized elderly rats

Studies have shown a strong relationship between menopause, diet, physical inactivity and presence of risk factors causing endothelial and tissue damages, leading to increased risk of developing cardiovascular disease. The aim of this study was to investigate the influence of resistance training on the effects of estrogen deprivation in aortic collagen and elastic tissue in aging. Fifteen Wistar female rats, 4 months-old, average weight 240 g were studied. All animals were ovariectomized at 6 months of age, after divided into 3 groups (n = 5): Sedentary adult (13 months), Sedentary old and Trained old (both with 17 months). All animals were ovariectomized at 6 months of age. The animals were observed for 8 months after its ovariectomy and then submitted to resistance training protocol during 12 weeks. At the end of the experiment the animals were euthanized. Samples of the ascending aorta were sectioned, fixed, processed and stained for examination by light microscopy. Photomicrographs were used for stereological study and analyzed the following parameters: body weight, volume density of collagen fibers and elastic lamellae. No significant difference was found between the initial and final weights in the studied groups. Resistance training attenuates the increase in volume density of elastic lamellae (21%) and collagen fibers (16%), when compared with the sedentary older group.

Influence of resistance training in left ventricle of ovariectomized elderly rats

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 causesbiochemical, electrical, morphological, and mechanical adaptations in the cardiac muscle, which togetherprovide an improvement in the cardiac function. The goal of the present study was to evaluate theeffect of resistance training in the left ventricle of ovariectomized rats through stereological analysis. Westudied  15  Wistar female rats, 4 months- old, average weight 240 g. All animals were ovariectomized at9 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 TrainedElderly (17 months) (OTE). The rats were monitored for 13 months and subsequently underwent resistancetraining for 12 weeks. The stereological analysis was performed using light microscopy techniques and dataobtained 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 fibersfollowed 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 deprivedof ovarian hormones.