Effects of Different Swimming Intensities on the Bone Properties of the Tibia and Femur of Wistar Rats in which Knee Rheumatoid Arthritis was Induced

Abstract

Rheumatoid arthritis (RA) is a disease triggered by environmental and genetic factors. Research suggests that physical exercise has benefits such as delaying functional disability. In vivo studies using experimental models of arthritis can provide useful information about these benefits. to analyze the effects that different intensities of aquatic physical exercise have on the proprieties of the bones in induced arthritis in knees of Wistar rats. Male Wistar adults rats (n=20) were divided into 5 groups: Group Control Arthritis (GCA) n=4, Group control Placebo (GCP) n=4, Group Low Physical Activity (GB) n=4, Group Moderate Physical Activity (GM) n=4 and Group Intense Physical Activity (GI) n=4. The physical activity groups got an intra-articular injection of Zymosam on the right knee; the GCA received saline solution in the right knee; the GCP was submitted to the stress of the needle. The animals were submitted to aquatic activity for 30 minutes, 4 times a week for 5 weeks, and the intensity of the exercise was determined by a weight placed on their back: GB=1 %, GM=5 %, GI=15 % of their body weight. It was observed that the group GB, and the groups that did not exercise GCA and GCP, gained more weight compared to the group GM. In relation to the bone mineral content of the tibia, there was a decrease in the GM group when compared to the GCP group, whereas in the tibial bone mineral density there was a decrease in the GM group compared to the GCP, GCA, GB. As for the area of the femur, the GI group presented an increase of it compared to the GB and GM groups. It is concluded that the high intensity exercises promote better results in bone properties.

Benefits of electroacupuncture and a swimming association when compared with isolated protocols in an osteoarthritis model

“…Notably, Mioto et al. 40 did not find any difference in the improvement of bone features of rats that received Zymosan into the knee and were submitted to different intensity of aquatic exercise for 5 weeks. On the other hand, a mild intensity swimming protocol in rats, three times per week, from 5 to 15 min for 4 weeks, revealed no aggravation of arthritis, besides no decrease on the response to paw pressure were observed in those animals.…”

“…Hydrotherapy is commonly used during the rehabilitation process, although there is no standard physical exercise protocol for OA treatment. 40 Thus, the present study decided to use low intensity EA even when associated therapy was applied. Notably, Mioto et al.…”