Researchers found that walking 6,000 or more steps per day may protect those with or at risk of knee OA from developing mobility issues, such as difficulty getting up from a chair and climbing stairs.
Previous research has found that knee OA is the leading cause of functional limitation among older adults, making walking and climbing stairs difficult.
"Our study examines if more walking equates with better functioning, and if so, how much daily walking is needed to minimise risk of developing problems with mobility in people with knee OA," said Daniel White from Sargent College at Boston University in Massachusetts.
For the present study, researchers measured daily steps taken by 1,788 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 between a 16 per cent to 18 per cent reduction in incident functional limitation two years later.
Walking less than 6,000 steps daily was the best threshold for identifying those who developed functional limitation.
"Walking is an inexpensive activity and despite the common popular goal of walking 10,000 steps per day, our study finds only 6,000 steps are necessary to realise benefits," White said.
"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 minimise the risk of developing difficulty with mobility," White added.
The study was published in the American College of Rheumatology (ACR) journal, Arthritis Care & Research.