Effect of swimming on clinical functional parameters and serum biomarkers in healthy and osteoarthritic dogs.

This study aimed to determine whether swimming could improve function of osteoarthritic joints in canine hip OA. Fifty-five dogs were categorized into three groups. The OA with swimming group (OA-SW; n = 22), the healthy (non-OA; n = 18) with swimming group (H-SW), and the healthy (non-OA; n = 15) without swimming group (H-NSW). All animals were allowed to swim for a total of 8 weeks (2-day period, 3 cycles of swimming for 20 minutes, and resting period for 5 minutes in each cycle). Three ml of blood was collected every 2 weeks for evaluation of the levels of biomarkers for OA, including chondroitin sulfate epitope WF6 (CS-WF6) and hyaluronan (HA). Clinical evaluation of the OA-SW group found that most parameters showed improvement (P < 0.01) at week 8 compared to pretreatment, while pain on palpation was improved (P < 0.01) at week 6. The relative level of serum CS-WF6 in the OA-SW group was found to be significantly different (P < 0.01) at weeks 6 and 8 compared with the preexercise. The levels of serum HA of the H-SW group in weeks 2-8 were significantly (P < 0.01) higher than preexercise. Conclusion, swimming over 2-day period, 8 weeks continually, can improve the function of OA joint.