Osteoarthritis is a common degenerative joint disease that causes pain, stiffness and swelling, and reduces your range of motion. It often affects the knees, hips and hands, although it can also occur in other joints throughout the body.
If you’ve been diagnosed with osteoarthritis, your doctor has probably recommended exercise. This has become standard treatment advice in recent years.
However, a new review suggests exercise might not be as beneficial as first thought.
But when you take a closer look at the study, there are reasons to be cautious. So it shouldn’t prompt you to ditch your exercise regimen.
The research team conducted an “umbrella review” – an overview of systematic reviews, which collate and analyse the findings from individual studies to answer a specific question. Reviewing previously published systematic reviews provides an even bigger snapshot of a given research topic.
After searching thousands of studies, they included five major systematic reviews (comprised of 100 individual studies, with 8,631 patients) before adding another 28 recent trials (involving another 4,360 patients).
Using this data, they looked at the effect of exercise on knee, hip and hand osteoarthritis, and compared it to several alternatives, including doing nothing, placebo (fake) treatments, education, manual therapy, painkillers, injections and surgery.
What did they find?
Compared to doing nothing and placebos, they found that exercise resulted in small reductions in pain in the hip, knee and hand: between 6 and 12 points on a 100-point scale.
However, exercise did not seem to improve function any more than either of these comparisons.
For knee and hip osteoarthritis, there was evidence that exercise was just as effective at reducing pain and improving function as medicines such as ibuprofen and corticosteroids, which are injected into the joint to reduce inflammation. These also reduced pain by around 5–10%.
The researchers concluded exercise was less effective at improving pain and function than a total joint replacement in people with knee and hip osteoarthritis.
What were the limitations?
First, the authors lumped all types of exercise together. This means strength training, aerobic exercise, stretching, aquatic exercise and tai chi were all considered to be the same.
This is crucial, because we know not all exercise is created equal. Previous reviews have shown, for example, that aerobic exercise might be best for reducing pain and function in people with knee osteoarthritis, while stretching was least effective.
Similarly, the authors didn’t consider the clinical status of the patients. Evidence has shown people with more severe pain and worse function at the start of an intervention see better responses to exercise than those with less pain and good function.
Second, the review treated both supervised and unsupervised exercise the same.
However, research shows supervised training results in much better outcomes than unsupervised – likely because a trainer is there to help push the patient along.
Third, the authors didn’t account for the duration of the exercise, and most study periods were quite short: around 12 weeks.
It’s likely that sticking to an exercise regime over the long term will have better results, leading to a larger scope for improvement than if you just did something for a few weeks.
As such, the results of this review may not accurately reflect the benefits of exercise in people with osteoarthritis who commit to consistent exercise as an ongoing part of their weekly routine (which is often recommended).
Finally, the review didn’t account for the dose of exercise the studies used. Improvements in pain and function seem to increase with total weekly exercise in people with osteoarthritis. One review, for example, found the optimal benefits occurred at around 150 minutes of moderate intensity exercise per week.
These limitations suggest this new review likely undersells the benefits of exercise for osteoarthritis.
Less pain and better mental and physical health
Putting aside the limitations of the review, the small reductions in pain the review reports might still have a positive impact on someone’s life. A 10% reduction in pain could make a meaningful difference to your ability to move around, work, socialise and care for others.
The review also found exercise can reduce pain to the same extent as non-steriodal anti-inflammatory medications and corticosteroids – without the side-effects or the costs.
Exercise can also improve heart health, enhance your mood, help with weight management and reduce the risk of chronic diseases, such as cancer and diabetes.
These factors can have a huge impact on your health and happiness.
What should you do now?
Based on the findings of this new review, you should be confident that any type of exercise will lead to some degree of pain relief.
However, based on prior evidence, it’s likely you can get even greater overall health benefits from exercising if you stick with it.
The best type of exercise is the one that gets done. If you enjoy being outdoors and walking, then this is going to be a great choice as it will improve all aspects of your health as well as reduce pain.
And if pain permits, don’t be afraid to occasionally challenge yourself by upping the intensity to the point where holding a conversation starts to become difficult.
If going to the gym is more your thing, lifting weights will also bring significant overall health benefits – especially if you stick to it long term.
Hunter Bennett, Lecturer in Exercise Science, Adelaide University and Lewis Ingram, Lecturer in Physiotherapy, Adelaide University
This article is republished from The Conversation under a Creative Commons license.