title: Accelerometer monitoring of home- and community-based ambulatory activity after stroke.
abstract: OBJECTIVE
  To investigate the utility of a novel microprocessor-linked Step Watch Activity Monitor (SAM) to quantify ambulatory activity after stroke and to evaluate the validity and reliability of conventional accelerometers to measure free-living physical activity in this population.
  
  
  METHODS
  Cross-sectional with repeated measures of 2 separate 48-hour recordings in 17 persons wearing an ankle-mounted SAM and Caltrac, a hip-mounted mechanical accelerometer.
  
  
  METHODS
  Home and community.
  
  
  METHODS
  Seventeen subjects with chronic hemiparetic gait after stroke.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  The SAM derived stride counts per day and Caltrac estimated the daily caloric expenditure of physical activity.
  
  
  RESULTS
  SAM data revealed that stroke patients had a mean strides per day +/- standard deviation of 3035+/-1944 and demonstrated a broad range of daily activity profiles (400-6472 strides). SAM test-retest reliability was high across separate monitoring periods (r=.96, P<.001). Although Caltrac also revealed a broad range of daily activity calories (346+/-217 kcal/d; range, 83-1222 kcal/d), reliability was poor (r=.044, P=not significant) and Caltrac accounted for only 64% of the ambulatory activity quantified by the SAM.
  
  
  CONCLUSIONS
  Microprocessor-linked accelerometer monitoring, but not conventional accelerometers, are accurate and highly reliable for quantifying ambulatory activity levels in stroke patients. These findings support the utility of personal status monitoring of ambulatory activity as an outcomes instrument and metric in programs to increase physical activity and cardiovascular health after stroke.
authors.affiliation: Baltimore Veterans Affairs Medical Center Geriatrics Research, Education and Clinical Center, MD, USA.
authors.forename: Elaina
authors.initials: E
authors.lastname: Haeuber
authors.forename: Marianne
authors.initials: M
authors.lastname: Shaughnessy
authors.forename: Larry W
authors.initials: LW
authors.lastname: Forrester
authors.forename: Kim L
authors.initials: KL
authors.lastname: Coleman
authors.forename: Richard F
authors.initials: RF
authors.lastname: Macko
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D003430:Cross-Sectional Studies; D004734:Energy Metabolism / Q000502:physiology; D005240:Feasibility Studies; D020233:Gait Disorders, Neurologic / Q000503:physiopathology* / Q000534:rehabilitation; D006801:Humans; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D009043:Motor Activity / Q000502:physiology*; D015203:Reproducibility of Results; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation