Osteoarthritis (OA) is a degenerative joint disease that occurs when the cartilage cushioning the ends of bones wears down, leading to symptoms such as swelling, stiffness, and discomfort. While it can impact any joint, the knees are the most commonly affected. Research indicates that approximately 30% of adults over the age of 45 exhibit signs of knee osteoarthritis on x-rays, with nearly half facing significant pain and mobility challenges.
Exercise is a fundamental component of osteoarthritis care; however, many medical guidelines lack specific recommendations regarding the most effective exercise types for knee osteoarthritis. To address this gap, researchers conducted an extensive analysis of the effectiveness and safety of various exercise approaches. Their comprehensive study examined 217 randomized clinical trials spanning from 1990 to 2024, involving a total of 15,684 participants and comparing different exercise categories, including aerobic, flexibility, strengthening, mind-body, neuromotor, and mixed programs against control groups.
The trials reviewed varied in quality; however, the research team utilized the internationally recognized GRADE system to assess the strength of the evidence. They focused on several key outcomes, including pain reduction, physical function, gait performance, and quality of life, measured over short-term (four weeks), mid-term (12 weeks), and long-term (24 weeks) follow-ups. Notably, aerobic exercise consistently emerged as the most effective option for improving outcomes across all exercise types.
Moderate-certainty evidence indicated that aerobic exercise significantly reduced pain in both the short- and mid-term while enhancing functional capacity over both short- and long-term periods. Additionally, it improved gait performance and quality of life during short and mid-term assessments. Other types of exercise also demonstrated benefits; for instance, mind-body workouts were likely to enhance short-term function, neuromotor exercises showed potential for improving short-term gait performance, and strengthening or mixed routines contributed to mid-term functional improvements.
Importantly, none of the exercise types resulted in a higher incidence of adverse events compared to control groups, highlighting the overall safety of these therapies. The authors acknowledged certain limitations in their study, including reliance on indirect comparisons, a lack of long-term data for some outcomes, and potential influences from smaller studies on initial findings.
Despite these limitations, the researchers consider their work one of the most thorough and up-to-date evaluations of exercise for managing knee osteoarthritis. They assert that these findings will assist clinicians in making more informed recommendations. Based on the evidence, the team recommends aerobic exercise as the first-line intervention for managing knee osteoarthritis, particularly aimed at improving functional capacity and alleviating pain. Furthermore, if aerobic exercises are not feasible due to individual limitations, alternative forms of structured physical activity may still provide significant benefits.
