Water Exercise Offers Gentle Relief for Knee and Hip Osteoarthritis

For people living with knee or hip osteoarthritis, exercising in a swimming pool is often suggested as a gentler alternative to exercising on land. A Cochrane systematic review pooled the evidence from randomized trials to see whether water-based exercise actually helps.

What the research looked at

The review combined 13 randomized controlled trials involving a total of 1,190 participants with knee and/or hip osteoarthritis. These trials compared structured aquatic exercise programmes — typically supervised sessions performed in a pool — against no exercise or other comparison groups, measuring outcomes such as pain, physical disability, and quality of life.

What it found

Based on moderate-quality evidence, the review found that aquatic exercise led to small but clinically relevant short-term improvements. On 0-to-100 scales, participants who did water-based exercise reported pain and disability scores that were, on average, about 5 points lower than those who did not exercise in water, along with quality-of-life scores that were about 7 points higher. These are modest shifts, not dramatic ones, but the review authors judged them large enough to matter to people living with day-to-day joint pain.

The likely explanation is straightforward: water's buoyancy supports much of the body's weight, which reduces the load carried by the knee and hip joints during movement. That can make it possible to move, stretch, and strengthen the muscles around a joint with less pain than the same movements would cause on land.

What it means (and the limits)

These findings suggest that aquatic exercise is a reasonable, gentle option for people with knee or hip osteoarthritis, particularly those who find land-based exercise too painful or difficult to start with. Because the improvements were measured in the short term, the review does not tell us how long the benefits last, and moderate-quality evidence means there is still some uncertainty around the exact size of the effect.

Aquatic exercise is not a cure for osteoarthritis. It is best seen as one part of a broader approach to managing joint health, alongside guidance from a doctor or physiotherapist. It will not suit everyone, and people should check with their doctor before starting a new exercise programme, especially if they have other health conditions.

Sources: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD005523.pub3/full · https://www.cochrane.org/CD005523/MUSKEL_aquatic-exercise-people-osteoarthritis-knee-or-hip

This is a plain-language summary of published research for general education. It is not medical advice, a diagnosis, or a treatment recommendation, and individual studies have limitations. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Consult your doctor or pharmacist about your own situation.