Walking at least 6000 steps a day may be the ideal amount of physical activity to help ward off mobility problems from knee osteoarthritis, according to new research.
Previous studies have reported that osteoarthritis in knees is the leading cause of functional limitations among older adults, making walking and climbing stairs difficult. Additional research has shown that a physically active lifestyle including structured exercise can be therapeutic for arthritic knees.
But investigators in a large, multicenter, longitudinal study of older adults with or at risk of knee osteoarthritis wanted to know whether unstructured activity such as walking could reduce the likelihood of functional limitations.
Enrolled in their study were 1788 adults whose average age was 67 years. The participants had or were at risk of knee osteoarthritis based on x-rays and their own assessments of how much pain they felt. Each was given an ankle device that recorded the number of strides taken daily for 7 days as a baseline measurement. Two years later, investigators evaluated the participants’ walking speed and scores on a pain scale to determine whether their steps per day correlated with functional decline.
Their analysis, published online today in Arthritis Care & Research, showed that walking 5000 to 7499 steps daily halved the risk of developing functional limitations compared with participants who walked fewer than 5000 steps. Walking 7500 or more steps a day reduced the risk by 60% to 70% compared with fewer than 5000 steps. Every additional 1000 daily steps conferred a 16% to 18% reduction in risk. The investigators found that 6000 steps per day was the best threshold to determine which participants did or did not develop functional problems.
“Walking is an inexpensive activity and despite the common popular goal of walking 10 000 steps per day, our study finds only 6000 steps are necessary to realize benefits,” lead author Daniel White, PT, ScD, of Boston University in Massachusetts, said in a statement.
“We encourage those with or at risk of knee osteoarthritis to walk at least 3000 or more steps each day and ultimately progress to 6000 steps daily to minimize the risk of developing difficulty with mobility,” White added.
He and his colleagues wrote that their findings could be considered preliminary clinical recommendations for therapeutic physical activity targets for people with or at risk of knee osteoarthritis.