Karen Collins, MS, RDN, CDN
American Institute for Cancer Research
Q: Does exercise improve or worsen arthritis of the knees?
A: Osteoarthritis, the most common type of knee arthritis, is when cartilage in the knee breaks down due to wear-and-tear. Current clinical guidelines identify exercise as a core part of managing knee osteoarthritis. A wide body of research shows that exercise interventions can reduce pain, improve ability to function in daily life and improve people’s quality of life. Strengthening, flexibility and aerobic exercise all provide benefit, and best results seem to come when all three are made part of a regular lifestyle. Strength-training (also called resistance exercise) not only builds muscle strength, it helps improve mechanics of how the knee joint moves and may normalize the way muscles fire, reducing joint pain and further cartilage destruction. However, individual differences in the severity of arthritis and its specific location matter, so it’s essential you get recommendations and monitoring by your doctor, physical therapist or other qualified health care professional.
Clinical guidelines for treating knee osteoarthritis also recommend weight loss for those who are overweight. Excess weight puts strain on the knees and is a risk factor for developing knee osteoarthritis. In a clinical trial of overweight and obese people with mild to moderate knee osteoarthritis, the group assigned to both diet and exercise, rather than exercise alone, had less inflammation, less pain, better functioning and improved quality of life. When people lost 10 percent or more of their starting weight they got the greatest reduction in inflammation and pain.
The American Institute for Cancer Research (AICR) is the cancer charity that fosters research on the relationship of nutrition, physical activity and weight management to cancer risk, interprets the scientific literature and educates the public about the results. It has contributed more than $96 million for innovative research conducted at universities, hospitals and research centers across the country. AICR has published two landmark reports that interpret the accumulated research in the field, and is committed to a process of continuous review. AICR also provides a wide range of educational programs to help millions of Americans learn to make dietary changes for lower cancer risk. Its award-winning New American Plate program is presented in brochures, seminars and on its website, www.aicr.org. AICR is a member of the World Cancer Research Fund International.
Published on October 15, 2013