Individuals with chronic low back pain have a lower level, and an altered pattern, of physical activity compared with matched controls: an observational study.

QUESTION Is there a difference in the level and pattern of free-living physical activity between individuals with chronic low back pain and matched controls? DESIGN Observational, cross-sectional study. PARTICIPANTS Fifteen individuals with chronic low back pain and fifteen healthy controls matched for age, gender, and occupation. OUTCOME MEASURES Participants wore an activity monitor for seven days. Level of physical activity was measured as time standing and walking, and number of steps averaged over a 24-hour day (midnight to midnight), day time (9.00 am - 4.00 pm), and evening time (6.00 pm - 10.00 pm), and work days versus non-work days. Pattern of physical activity was measured as number of steps and cadence during short (< 20 continuous steps), moderate (20-100 continuous steps), long (> 100-499 continuous steps), and extra long walks (>or= 500 continuous steps). RESULTS Over an average 24-hour day, the chronic low back pain group spent 0.7 fewer hours (95% CI 0.3 to 1.1) walking, and took 3480 fewer steps (95% CI 1754 to 5207) than the healthy controls. They took 793 fewer steps/day (95% CI -4 to 1591) during moderate walks, and 1214 fewer steps/day (95% CI 425 to 2003) during long walks, and 11 fewer steps/min (95% CI 4 to 17) during extra long walks than the healthy controls. CONCLUSION Individuals with chronic low back pain have a lower level, and an altered pattern, of physical activity compared with matched controls.