A major review of 217 clinical trials has identified aerobic exercises like walking, cycling and swimming as the most effective for reducing pain and improving function in knee osteoarthritis. The study, published in The BMJ, recommends these activities as the first-line intervention. Other exercises provide benefits but work best alongside aerobics.
Researchers analyzed 217 randomized trials from 1990 to 2024, involving 15,684 participants with knee osteoarthritis. The review compared aerobic, flexibility, strengthening, mind-body, neuromotor and mixed exercise programs against controls. Using the GRADE system, they assessed evidence quality across short-term (four weeks), mid-term (12 weeks) and long-term (24 weeks) outcomes, focusing on pain, physical function, gait and quality of life. Aerobic exercise consistently ranked highest, with moderate-certainty evidence showing pain reduction in short and mid-term, plus improvements in function, walking ability and quality of life during those periods. Strengthening and mixed programs aided mid-term function, while mind-body and neuromotor exercises helped short-term outcomes. No exercise type increased adverse events compared to controls, confirming safety. The findings address gaps in guidelines, as knee osteoarthritis affects nearly 30% of adults over 45 on x-rays, with half experiencing severe symptoms from cartilage breakdown. Researchers recommend aerobic exercise 'as a first line intervention for knee osteoarthritis management, particularly when the aim is to improve functional capacity and reduce pain.' If unsuitable, 'alternative forms of structured physical activity may still be beneficial.' Limitations include indirect comparisons and limited long-term data for some outcomes.