What are the best exercises for osteoarthritis (OA) of the knee?

From the Guidelines

The best exercises for osteoarthritis of the knee include low-impact activities such as walking, swimming, water aerobics, stationary cycling, and tai chi, which provide cardiovascular benefits while minimizing stress on the knee joint. These exercises are recommended based on the latest evidence from a 2023 network meta-analysis of randomized controlled trials, which found that exercise has similar effects on pain and function to that of oral non-steroidal anti-inflammatory drugs and paracetamol 1.

Key Exercises

• Low-impact aerobic exercises: walking, swimming, water aerobics, stationary cycling
• Strengthening exercises: straight leg raises, hamstring stretches, calf raises, gentle mini-squats (not going below 45 degrees)
• Tai chi: a low-impact, mind-body exercise that can help improve balance and reduce stress on the knee joint

Exercise Recommendations

• Aim for 30 minutes of aerobic exercise at least 5 days per week
• Incorporate strength training 2-3 times weekly, starting with 1-2 sets of 10 repetitions and gradually increasing as tolerated
• Always warm up for 5-10 minutes before exercising and cool down afterward
• Exercise should cause minimal discomfort that subsides quickly after stopping; sharp or increasing pain signals the need to modify or stop the activity

Benefits of Exercise

• Strengthens the quadriceps, hamstrings, and other supporting muscles, which helps stabilize the knee joint
• Improves shock absorption, increases range of motion, and reduces the load on damaged cartilage
• Promotes weight management, which further reduces stress on the knee joints
• Stimulates the production of synovial fluid, which lubricates the joint

According to the 2019 American College of Rheumatology guideline for the management of osteoarthritis of the hand, hip, and knee, exercise is a core treatment for knee osteoarthritis, and patients should participate in a regular, ongoing exercise program 1. The guideline also recommends weight loss for patients with knee and/or hip osteoarthritis who are overweight or obese. A 2009 study published in the Journal of the American Academy of Orthopaedic Surgeons recommends low-impact aerobic fitness exercises for patients with symptomatic osteoarthritis of the knee 1.

From the Research

Best Exercises for Osteoarthritis Knee

• The optimal type or dose of therapeutic exercise for managing knee osteoarthritis (KOA) is not currently known, however, all exercise modalities proved similarly beneficial at managing KOA with comparable improvements to knee pain, stiffness, and physical function 2.
• Benefits to KOA management were observed in everyone, including the elderly, obese, and those with severe KOA, although walking was observed to only prevent further deterioration in those with severe KOA, rather than induce any symptomatic improvement 2.
• Moderate intensity exercise performed three times weekly for 20-to-60-min appears optimal for KOA symptom control following most exercise modalities 2.
• Both strengthening and aerobic exercise showed positive effects, and both aquatic and land-based programmes presented improvement of pain, physical function, and quality of life 3.
• Pilates, aerobic, and strengthening exercise programmes performed for 8-12 weeks, 3-5 sessions per week, each session lasting 1 h, appear to be effective 3.

Specific Exercises

• Strengthening of the hamstrings in addition to strengthening of the quadriceps was shown to be beneficial for improving subjective knee pain, range of motion, and decreasing the limitation of functional performance of patients with knee osteoarthritis 4, 5.
• Strengthening the hamstring muscles in addition to strengthening the quadriceps muscles proved to be beneficial for perceived knee pain, range of motion, and decreasing the limitation of functional performance of patients with knee OA 5.

General Recommendations

• Therapeutic exercise is safe for patients with knee and hip OA, and numerous types of therapeutic exercise may be utilized at varying doses and in different settings to improve pain and function 6.
• Benefits from therapeutic exercise appear greater when dosage recommendations from general exercise guidelines for healthy adults are met 6.
• Theoretically-informed strategies to improve adherence to therapeutic exercise, such as patient education, goal-setting, monitoring, and feedback, may help maintain participation and optimize clinical benefits over the longer term 6.