title: Free-living physical activity in COPD: assessment with accelerometer and activity checklist.
abstract: To assess physical activity and disability in chronic obstructive pulmonary disease (COPD), we evaluated the use of an accelerometer and checklist to measure free-living physical activity. Seventeen males with stable COPD completed a daily activity checklist for 14 days. Ten subjects concurrently wore an Actiped accelerometer (FitSense, Southborough, Massachussetts) that records steps per day. Regression models assessed relationships between steps per day, number of daily checklist activities performed, and clinical measures of COPD status. The average steps per day ranged from 406 to 4,856. The median intrasubject coefficient of variation for steps per day was 0.52 (interquartile range [IQR] 0.41-0.58) and for number of daily checklist activities performed was 0.28 (IQR 0.22-0.32). A higher number of steps per day was associated with a greater distance walked on the 6-minute walk test and better health-related quality of life. A higher number of daily checklist activities performed was associated with a higher force expiratory volume in 1 s percent predicted and lowerbody mass index, airflow obstruction, dyspnea, exercise capacity (BODE) index. Prospectively measuring free-living physical activity in COPD using an unobtrusive accelerometer and simple activity checklist is feasible. Low intrasubject variation was found in free-living physical activity, which is significantly associated with clinical measures of COPD status.
authors.affiliation: Department of Veterans Affairs, Veterans Health Administration, Rehabilitation Research and Development Service, Boston, MA, USA. marilyn.moy@va.gov
authors.forename: Marilyn L
authors.initials: ML
authors.lastname: Moy
authors.forename: Kirby
authors.initials: K
authors.lastname: Matthess
authors.forename: Kelly
authors.initials: K
authors.lastname: Stolzmann
authors.forename: John
authors.initials: J
authors.lastname: Reilly
authors.forename: Eric
authors.initials: E
authors.lastname: Garshick
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D017079:Exercise Tolerance; D005541:Forced Expiratory Volume; D006304:Health Status; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D014797:Vital Capacity; D016138:Walking