Online Tai Chi for Knee Osteoarthritis: What the RETREAT Trial Shows

Part of the Tai Chi for Arthritis Hub — see the OA vs RA evidence summary and our safe starting routine.

Knee osteoarthritis (OA) is a global challenge, causing chronic pain and limited mobility for millions. While exercise is a cornerstone of its management, traditional in-person tai chi classes can be out of reach because of location, cost, or time. A landmark clinical trial from Australia, published in JAMA Internal Medicine, asked whether a completely online, video-based tai chi program could still deliver real, clinical benefits — and it did.

The Study: Design and Delivery

The RETREAT trial, led by Professor Kim Bennell at the University of Melbourne, was a randomized controlled trial built to a rigorous standard. The researchers recruited 178 adults with knee osteoarthritis and split them into two groups:

• One group received access to a website about managing osteoarthritis.
• The other group received the same education plus a 12-week online Yang-style Tai Chi program, hosted on the MyJointTaiChi platform, with a new 45-minute video each week and the recommendation to practice three times per week.

What makes this trial so important is that it was completely unsupervised — no live instructor. If online-delivered tai chi could work here, it would open the door for anyone to practice safely at home.

The Results: Significant Pain and Function Gains

After 12 weeks, the tai chi group showed clear advantages:

• Pain reduction. On a 0-10 scale, the tai chi group’s pain decreased by an average of 2.7 points, compared with 1.3 points in the control group. Crucially, 73% of tai chi participants experienced a level of pain relief they considered a meaningful, clinical improvement.
• Improved function. On the standard WOMAC functional assessment, the tai chi group’s physical function improved by 12.0 points — a significantly greater gain than the control group. Again, 72% of participants felt a clinically important improvement in their ability to perform daily activities.
• Beyond pain and function. The tai chi group also showed better scores in quality of life and mental health. Importantly, the program was safe, with no serious adverse events reported.

Equally striking is what the online format made possible. Participants practiced an average of 2.5 times per week with high satisfaction scores (9/10). This proves that a well-structured, video-based program can foster excellent adherence and deliver tangible health outcomes without a live instructor.

Why This Matters for Knee OA

The slow, flowing, continuous movements of Yang-style tai chi are precisely what make it suitable for a damaged knee. The practice strengthens the muscles that support the knee through gentle weight-shifting, without the impact of running or jumping. The RETREAT results — comparable to what previous trials found with supervised tai chi and strength training — indicate that the benefits are not only about muscle strength, but also about proprioception, joint stability, and the mind-body connection.

For anyone hesitant to join a class because of an aching knee, time, or distance, this is meaningful evidence: you can begin gently and safely at home, at your own pace, on a regular schedule.

The Honest Takeaway

This is a strong, well-designed trial for knee osteoarthritis specifically — not a cure claim, and not a blanket claim for every form of arthritis. It shows that online Yang-style tai chi is an effective, safe, and sustainable complement for knee OA pain and function. For readers managing osteoarthritis, that is genuinely good news; for those with rheumatoid arthritis, the evidence is different and complementary, as our Tai Chi for Arthritis Hub explains honestly.

Disclaimer: This article is for educational purposes only and does not replace professional medical advice. Always consult a qualified healthcare provider before starting any exercise program, especially if you have severe arthritis, mobility limitations, or other chronic conditions.