A study confirms what people with knee and hip osteoarthritis (OA) have known all along – aquatic exercise can help relieve pain and improve daily function.

The study, which appears in The Cochrane Library, analyzed six trials with a collective 800 participants with OA. Four studies included patients with OA of either the knee or hip, one study followed patients with only hip OA and one included patients with only knee OA.

In the studies, some patients did aquatic exercises for different lengths of time and numbers of sessions per week, while others did no exercise or exercised on land. Most of the studies measured patients after three months of therapy.

Based on the studies’ results, the reviewers said, “In people with osteoarthritis of the hip or knee, pain may decrease by one more point on a scale of 0 to 20 with aquatic exercise, and function may improve by three more points on a scale of 0 to 68.”

Based on these findings the study’s authors say, “one may consider using aquatic exercise as the first part of a longer exercise program for osteoarthritis patients.”

The Cochrane Library is a publication of The Cochrane Collaboration, an international organization that evaluates research in all aspects of health care.