A new study shows that walking 6,000 or more steps per day may protect those with or at risk of knee osteoarthritis from developing mobility issues, such as difficulty getting up from a chair and climbing stairs. The research appears in the current issue of Arthritis Care & Research.
Although walking has many known health benefits, the Centers for Disease Control and Prevention reported that two-thirds of U.S. adults with arthritis walk fewer than 90 minutes each week.
“Our study examines if more walking equates with better functioning, and if so, how much daily walking is needed to minimize risk of developing problems with mobility in people with knee OA,” said lead researcher Daniel White, P.T., Sc.D., of Boston University.
Osteoarthritis is the leading cause of disability among those age 65 and over according to the Agency for Healthcare Quality and Research. It is the most prevalent form of arthritis in the United States, affecting more than 20 million adults. More than half of all people age 65 and over have evidence of this condition.
According to the Arthritis Foundation, OA is the leading cause of years lived with a disability in the U.S., with nearly one million years lived with disability from hip and knee pain. Data from the National Health and Nutrition Examination Survey (NHANES III) show that 80 percent of OA patients have some limitation in movement.
Additionally, 11 percent of adults with knee OA need assistance with personal care, about 25 percent of have pain on walking and have difficulty doing major activities of daily living (ADLs) such as walking a quarter mile, climbing stairs, kneeling or stooping and 15 percent have to use an assistive device such as a cane or crutch for walking. Symptoms typically begin at around age 40, but after age 50, women tend to be more affected than men.
In this new study, researchers measured daily steps taken by 1788 people with or at risk for knee OA, who were part of the Multicenter Osteoarthritis Study. Walking was measured with a monitor over seven days and functional limitation evaluated two years later, defined as a slow walking speed and a Western Ontario and McMaster Universities Arthritis Index (WOMAC) physical function score greater than 28 out of 68.
Walking an additional 1,000 steps each was associated with a 16 percent to 18 percent reduction in incident functional limitation two years later. Walking fewer than 6,000 steps daily was the best threshold for identifying those who developed functional limitation, the study showed.
Traditionally, clinicians have relied heavily on the use of non-steroidal anti-inflammatory drugs (NSAIDs) to treat the pain of OA, as an effective treatment for pain and stiffness. However, the cardiovascular, gastrointestinal, renal and hepatic toxicities of NSAIDs have limited their use, particularly in the elderly.
Researchers are investigating some of the underlying factors contributing to severity of OA such as genetics, body fat and trauma, which may lead to new therapies and approaches.
In the meantime, White advised those with knee OA to lace up their walking shoes. “Despite the common popular goal of walking 10,000 steps per day, our study finds only 6,000 steps are necessary to realize benefits. We encourage those with or at risk of knee OA to walk at least 3,000 or more steps each day, and ultimately progress to 6,000 steps daily to minimize the risk of developing difficulty with mobility.”
