The Effects of Resistance Exercise on the Cardiorespiratory Tissue of Rats with Parkinson's Disease.

Parkinson's Disease (PD) affects the cardiorespiratory system, causing an increase in the left ventricular mass in the heart and respiratory muscle weakness in relation to healthy individuals. The objective of this study was to investigate the effects of progressive resistive physical exercise on the vertical ladder on the histomorphometry of cardiac tissue and respiratory muscles in rats with PD. Seventy male Wistar rats, aged 40 days old, were divided into Parkinson's (PD) and Sham (SH) groups; they were also subdivided into groups that performed progressive resistive physical exercise on the vertical ladder Before Surgery (ExBS), After Surgery (ExAS), and Before and After Surgery (ExBAS). The physical training was carried out before and/or after PD induction. Exercise was performed five times a week for 25 min/day for four or eight weeks. PD induction was conducted via electrolytic stimulation of the Substantia nigra of the animals' brains, adopting the following stereotaxic table coordinates: -4.9; lateral medium equal to 1.7, and dorsoventral equal to 8.1. For the morphometric analysis of the heart, the following variables were calculated: relative weight and diameter and thickness of the left ventricle. The diaphragm and the myocardial, intercostal, and abdominal muscles were stained with Hematoxylin and Eosin (HE). The histomorphometric analysis was performed using the ImageJ software to assess the cross-sectional area of muscles and the number of muscle fibers. Progressive resistance exercise promoted the hypertrophy of respiratory muscles and the left ventricle in animals with PD.

High Intensity Physical Exercise before the Brain Ischemia Promotes Increase in Brain Injury.

Studies have demonstrated the beneficial effects of light- and moderate-intensity physical exercise on the nervous system of animals with cerebral ischemia. To investigate the effects of two high-intensity physical exercise protocols, standardized for resistance and strength gain, in rats trained before cerebral ischemia induced by Bilateral Common Carotid Artery Occlusion (BCCAO). Forty-eight male Wistar rats were divided into two groups: with ischemia and without ischemia (sham). Both groups were subdivided into animals that performed high-intensity exercises in the muscle strength modality (I+Ex2; Sham+Ex2; n=16); animals submitted to high-intensity exercises in the aerobic modality (I+Ex1; Sham+Ex1; n=16), and animals that did not practice physical exercises - sedentary (I+Sed; Sham+Sed, n=16). Cerebral ischemia was induced using the BCCAO model. The physical training program used before the procedure was of high intensity, in the aerobic and muscular strength modalities, and was performed using a vertical ladder, for 4 weeks, 5 days per week. In order to process and stain the brain tissue, the Nissl method was used for neuron labeling and quantification in the cortex, striatum, and hippocampus. As for the animals' body weight and the heart weight differences were found between the groups I+Ex2 and Sham+Ex2 (p<0.05). Data on neuron quantification in the cerebral cortex, dentate gyrus, and right and left striatum revealed significant differences between groups. High-intensity physical training in the strength gain modality promotes significant damage to the animal's brain when performed prior to BCCAO-induced cerebral ischemia.