title: Using step activity monitoring to characterize ambulatory activity in community-dwelling older adults.
abstract: OBJECTIVE
  To explore the potential of using step activity monitoring to detect differences in ambulatory activity associated with advancing age and declining function in community-dwelling seniors.
  
  
  METHODS
  Cross-sectional pilot study.
  
  
  METHODS
  General communities of Seattle, Washington; Catonsville, Maryland; and Durham, North Carolina.
  
  
  METHODS
  Thirty healthy younger adults, 28 healthy older adults, and 12 older adults reporting functional limitations.
  
  
  METHODS
  Ambulatory activity data were collected over 6 days with the StepWatch 3. Average daily values were calculated for number of steps, number of minutes of activity, number of activity bouts, variability of minute-to-minute activity, and randomness of minute-to-minute activity fluctuations.
  
  
  RESULTS
  Healthy older adults engaged in fewer bouts of activity (P=.03) and displayed less-variable activity (P=.02) than younger adults. Older adults reporting functional limitations not only engaged in fewer bouts of activity (P=.009) and less variable activity (P<.001) than younger adults, but also accumulated fewer total steps (P=.003) and minutes of activity (P=.008) and had less-random minute-to-minute activity fluctuations (P=.02).
  
  
  CONCLUSIONS
  Step activity monitoring data were useful for detecting differences in ambulatory activity according to age and functional limitation. Monitor-based measures reflecting patterns of ambulatory activity show promise for use in studies of physical functioning.
authors.affiliation: Department of Veterans Affairs Medical Center, Durham, NC 27705, USA. jim.cavanaugh@duke.edu
authors.forename: James T
authors.initials: JT
authors.lastname: Cavanaugh
authors.forename: Kim L
authors.initials: KL
authors.lastname: Coleman
authors.forename: Jean M
authors.initials: JM
authors.lastname: Gaines
authors.forename: Linda
authors.initials: L
authors.lastname: Laing
authors.forename: Miriam C
authors.initials: MC
authors.lastname: Morey
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D003201:Computers; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D051346:Mobility Limitation; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D005082:Physical Exertion; D010865:Pilot Projects; D016138:Walking / Q000502:physiology*