Walking to meet physical activity guidelines in knee osteoarthritis: is 10,000 steps enough?

Abstract

To study if step goals (eg, walking 10,000 steps a day) approximate meeting the 2008 Physical Activity Guidelines for Americans. Cross-sectional observational cohort. Community. People with or at high risk of knee OA (N=1788). None. Objective physical activity data were collected over 7 consecutive days from people with or at high risk of knee OA participating in the Multicenter Osteoarthritis Study. Using activity monitor data, we determined the proportion that (1) walked ≥10,000 steps per day, (2) met the 2008 Physical Activity Guidelines, and (3) achieved both recommendations. Of the subjects studied (mean age ± SD, 67±8y; mean body mass index ± SD, 31±6kg/m(2); 60% women), 16.7% of men and 12.6% of women walked ≥10,000 steps per day, while 6% of men and 5% of women met the 2008 Physical Activity Guidelines for Americans. Of those walking ≥10,000 steps per day, 16.7% and 26.7% of men and women, respectively, also met the 2008 Physical Activity Guidelines. Among this sample of older adults with or at high risk of knee OA, walking ≥10,000 steps a day did not translate into meeting public health guidelines. These findings highlight the disparity between the number of steps believed to be needed per day and the recommended time-intensity guidelines to achieve positive health benefits.