Dieting and exercise decrease knee pain and increase function when combined in people suffering from osteoarthritis (OA), according to a new study published in the Journal of the American Medical Association.
With only half of those seeking pharmacological treatment for knee OA experiencing a 30 percent reduction in pain and fewer still experiencing improved function, researchers from Wake Forest University set about determining a more effective form of therapy.
Specifically. the study's goal was to determine whether a 10 percent reduction in body weight through dieting either with or without exercise would result in greater mobility and less pain for individuals with moderate knee OA.
Of the 450 participants, those who dieted and exercised experienced an average of 51 percent reduction in pain, compared to 25-28 percent in those who only dieted or only exercised.
Furthermore, the study showed that nearly 40 percent of those who dieted and exercised reported feeling little to no pain at the 18-month follow-up, versus 22 percent among those who only dieted and 28 percent among those who only exercised.
"We are not certain why the combined diet and exercise intervention was superior to either diet or exercise alone. It may be that there is a psycho-physiological effect of exercise on the central and peripheral nervous systems" Stephen Messier, a professor of health and exercise and co-author of the study, said in a statement. "What [the study] shows is that a weight loss of at least 10 percent is not only possible and safe for this population but when combined with exercise also leads to less pain, better mobility, and an improved health-related quality of life."
An estimated 250 million people worldwide suffer from debilitating knee OA, according to the researchers; the United States alone has seen a 162 percent rise in the number of knee replacement procedures during the last 20 years, amounting to $5 billion annually.
"The average time someone has to live with symptomatic knee OA is 26 years and approximately half those people end up with knee replacement surgery," Messier said. "Our purpose is not to replace surgery or pharmacological intervention but rather to provide a non-invasive treatment that will be part of the standard-of-care for people with knee OA and provide more years of independent living and a better quality of life."