Objective(s): Osteoarthritis (OA) or degenerative joint disease is the commonest form of arthritis and can lead to joint pain, decrease in joint’s range of motion, loss of function, and ultimately disability. Exercise is considered as one of the non-pharmacological treatments of OA. But the effects of exercise on knee joint cartilage remain ambiguous. The aim of the present study was to investigate the effect of a four-week moderate treadmill exercise on rats’ knee osteoarthritis. Materials and Methods: Eighteen male Wistar rats (173 ± 1 g, 8 weeks old) were randomly divided into three groups (n = 6): Intact control, monosodium iodoacetate (MIA) only (OA), and training. The osteoarthritis model was induced by intraarticular injection of monosodium iodoacetate (MIA). Subjects followed a moderate-intensity exercise program for 28 days. Rats were killed after 28 days and histological assessment was done on their knee joints. One-way ANOVA (P<0.05) and post-hoc Tukey test was used for the statistical analysis. Results: Histological assessment on 3 measurements of, depth ratio of lesions (P=0.001), total cartilage degeneration width ( P=0.001), and significant cartilage degeneration width (P=0.001), demonstrated that moderate exercise for 4 weeks could surprisingly almost treat OA symptoms of rats’ knee joints. Conclusion: The findings of the present study indicate that a moderate treadmill exercise program exert a beneficial influence on rats’ knee osteoarthritis.
