New research informs exercise selection for patients with knee osteoarthritis

A comprehensive BMJ network meta-analysis of 217 trials found that aerobic exercise demonstrates the strongest evidence for improving pain, function, gait performance and quality of life in knee osteoarthritis. Whilst other exercise modalities show benefits for specific outcomes, aerobic activities such as walking, cycling and swimming appear to offer the broadest therapeutic effects based on moderate certainty evidence.

A comprehensive network meta-analysis published in the BMJ has provided clarity on a question that often challenges physiotherapy practice: which type of exercise works best for knee osteoarthritis? The study by Yan and colleagues, which analysed 217 randomised controlled trials involving over 15,000 participants, found that aerobic exercise showed benefits across multiple outcomes. Compared to control groups, aerobic exercise demonstrated large improvements in pain relief, physical function, gait performance and quality of life at both short-term (4 weeks) and mid-term (12 weeks) follow-up periods, all supported by moderate certainty evidence.

Other exercise types showed benefits for specific outcomes too: mind-body exercise and neuromotor training improved function and gait performance respectively at short-term follow-up, whilst strengthening and mixed exercise programmes enhanced function at 12 weeks. There was no clear evidence of difference in safety between exercise interventions and control groups.

This review represents a significant methodological advancement over previous work. The researchers employed the updated Risk of Bias 2 tool and GRADE framework to assess evidence quality, stratified results across three time points rather than pooling all follow-up durations, and nearly doubled the number of included trials compared to the most recent comparable review from 2019. However, several limitations warrant consideration in clinical application. The majority of evidence came from indirect comparisons rather than head-to-head trials between different exercise types, which means we should interpret the relative benefits of different exercise modalities with caution. Long-term outcomes beyond 24 weeks were sparse, with only 23% of studies reporting follow-up at this duration and just 5.5% extending beyond 1 year. Given knee osteoarthritis is a chronic, progressive condition, this limits our understanding of sustained benefits. Additionally, most studies included participants across varying severity levels, making it difficult to determine whether exercise effectiveness differs according to disease stage.

For physiotherapists managing patients with knee osteoarthritis, these findings offer evidence to inform practice decisions. Consider aerobic exercise as a valuable intervention option when aiming to improve pain, function, gait performance and quality of life. Structured activities such as walking, cycling or swimming appear to offer benefits across multiple outcome measures. Individual tailoring remains essential. Whilst aerobic exercise shows promising combined benefits, other modalities – particularly neuromotor training for gait, mind-body exercise for function and mixed programmes – may be appropriate depending on patient preferences, comorbidities, mobility limitations and individual treatment goals. Consider the timeline when setting expectations with patients too, as the benefits of aerobic exercise appear most robust in the short to medium term (up to 12 weeks).

Structured programmes appear important, as the therapeutic effects observed came from planned, progressive exercise interventions rather than simply encouraging patients to “stay active.” Interestingly, the meta-regression analysis found that higher dose and intensity of exercise was not associated with greater treatment effects, suggesting that adherence and consistency may be more important than exercise volume alone. Remember that most evidence comes from indirect comparisons, long-term data is limited and exercise prescription should remain individualised and responsive to patient feedback.

This research has already been incorporated into relevant pages on Physiopedia, ensuring that healthcare professionals worldwide have access to the most current evidence. Physiopedia’s commitment to maintaining evidence-based content means that pages are regularly updated with new research findings like this BMJ study, helping bridge the gap between research publication and clinical practice.

This new study provides helpful evidence suggesting that aerobic exercise may offer broad benefits for knee osteoarthritis management. Whilst questions remain about optimal dosage, long-term sustainability and effects across different disease severities, the findings suggest that aerobic activity warrants consideration as a key component of exercise interventions for patients with knee osteoarthritis.