Pathological and structural study of cardiac striated muscle and quadriceps along with the study of microscopic changes in liver, kidney and lung tissue following short-term and long-term resistance exercises in male rats

Abstract

Background. Resistance exercise is a method designed to increase muscle strength and endurance, leading to beneficial physiological changes in various tissues. The aim of this study is to investigate the pathological and structural effects of short-term and long-term resistance training on various tissues of male rats, including cardiac striatum, quadriceps, liver, kidney, and lung tissue. Methods. Forty male Wistar rats were randomly divided into four groups: one-month control, four-month control, one-month exercise, and four-month exercise. After the exercise period, the animals were anesthetized and dissected to separate various tissues, which were then treated with formalin and prepared for analysis. Results. The study findings showed that liver tissue did not show significant histopathological changes in response to exercise. However, in the heart tissue, mild hyperemia and hypertrophy of muscle cells were observed in the exercise groups compared to the control groups. In the quadriceps muscle, hypertrophy was observed to a lesser extent in the one-month exercise group and to a greater extent in the four-month exercise group. There was a significant difference in the diameter of the muscle cells of the quadriceps muscle between the one-month and four-month exercise groups, indicating the beneficial effects of long-term exercise. Additionally, an increase in the size of the epithelial tissue of the urinary tubes was observed in both exercise groups, which indicates an increase in kidney function due to exercise. Conclusion. Overall, the results of this study show that resistance exercise can lead to beneficial physiological changes in various tissues, especially with long-term exercise. Understanding these changes can increase our knowledge about the benefits of exercise. Practical Implications. Resistance exercises, through actions such as hyperemia, hypertrophy of muscle cells, and hypertrophy of the epithelial tissue of urinary tubes, improve the efficiency of the heart, kidneys and muscles during sports exercises, especially with long-term exercise.