Who's a Lazybones? Physical Activity and Knee OA

Background
Adults with knee pain associated with osteoarthritis (OA) are generally assumed to be less physically active than healthy adults.

The studyThoma and colleagues1 looked at physical activity levels in 491 older adults (aged 50 to 85 years) with symptomatic knee OA and in 449 age-matched controls from the National Health and Nutrition Examination Survey. Study participants wore a uniaxial accelerometer for more than 10 hours a day for more than 4 days. The investigators calculated the time spent in moderate to vigorous physical activity.

Results
Time spent in moderate to vigorous physical activity was similarly low in older adults with symptomatic knee OA (median, 1 to 22 minutes per day) and in those from the general population without osteoarthritis or knee pain (median, 1 to 24 minutes per day).

Implications for clinicians
Because the general population is doing as little as individuals with knee pain that may hinder activity, the findings point to the need for efforts to increase physical activity for all.

"We were a little surprised to see similar low levels of physical activity in both those with and without painful knee arthritis. I think this is a wake-up call to everyone that we all need to be doing more activity," said senior author Dr. Daniel White, of the University of Delaware in Newark.

References:

1. Thoma LM, Dunlop D, Song J, et al. Are older adults with symptomatic knee osteoarthritis less active than the general population?: Analysis from the Osteoarthritis Initiative and NHANES.Arthritis Care Res. 2018 Feb 22. doi:10.1002/acr.23511. [Epub ahead of print]