Journal of Knowledge & Health in Basic Medical Sciences1735-577X14420200317Effects of Eight Weeks Aerobic Exercise on the Signaling Pathway of Cardiac Fibrosis in Elderly Rats485310.22100/jkh.v14i4.2324FAFatemehHttps:// Ph.D Student of Sport Physiology, Science and Research Branch, Islamic Azad University, Tehran, Iran.. fh.goodarzi@yahoo.comHosseinHttps://*Hojat OllahHttps:// Aging is a process that causes structural and functional changes in the heart. The purpose of the present study was to investigate the effect of eight weeks of aerobic training on the TGF-β / smads signaling pathway, which induces cardiac fibrosis in elderly rats.Methods: In this experimental study, 18 Wistar rats with age (24 months) and mean weight (511.15 g) were randomly divided into control (n=9) and exercise (n=9) groups. After adjusting to the environment and familiarizing with the practice, the task force performed their program on a treadmill with a steady zero degree slope at a constant speed of 12 m / min for eight weeks and 2 days a week. The training period ranged from 5 minutes in the first week to 52 minutes in the eighth week. The control group did not perform any exercise during this time. Research variables were measured by ELISA method using German ZellBio kit. Inferential t-test was used to analyze the data.Results: The results showed eight weeks of aerobic training on superoxide dismutase (P=0.001), catalase (P=0.006), glutathione peroxidase (P=0.012), transforming growth factor beta (P=0.001) and tissue collagen percentage had a significant effect on the heart tissue of elderly rats.Conclusion: The results showed that aerobic exercise was effective in improving cardiac oxidative stress indices by increasing the activity of antioxidant enzymes in cardiac tissue because, despite increasing TGF-β levels, it prevented the initiation of cardiac fibrosis signaling pathway, which Decreased collagen expression in the heart of aged rats.