title: Assessing the contribution of parks to physical activity using global positioning system and accelerometry.
abstract: OBJECTIVE
  Parks offer a free option for physical activity in many communities. How much time people spend using parks and the contribution that parks makes to their physical activity is not known. This study describes patterns of park use and physical activity among a diverse adult sample.
  
  
  METHODS
  From five US states, 248 adults enrolled in or near 31 study parks. Participants wore a global positioning system (GPS) monitor (Qstarz BT-Q1000X) and an ActiGraph accelerometer (GT1M) concurrently for 3 wk. Parks were mapped from local and national park shape files. Park visits and travel to and from the parks were derived from the objective data.
  
  
  RESULTS
  Participants visited parks a median of 2.3 times per week, and park visits lasted a median of 42.0 min. Overall, participants engaged in a median of 21.7 min·d-1 of moderate activity and 0.1 min·d-1 of vigorous activity, with an average of 8.2% of all moderate and 9.4% of all vigorous activity occurring within the parks. Among those with at least one park visit (n = 218), counts per minute, moderate, moderate-to-vigorous physical activity (MVPA), number and time in MVPA bouts per day, and sedentary behavior were all higher on days when a park was visited compared with days when a park was not visited. Considering several definitions of active travel, walking or bicycling to and from the park added an additional 3.7-6.6 mean minutes of MVPA per park visit.
  
  
  CONCLUSIONS
  Parks contributed as a place and destination for physical activity but were underused. One of the next steps in this line of inquiry is to understand characteristics of parks used more often as a place and destination for physical activity.
authors.affiliation: 1Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina-Chapel Hill, Chapel Hill, NC; 2Center for Health Promotion and Disease Prevention, University of North Carolina-Chapel Hill, Chapel Hill, NC; 3Department of City and Regional Planning, University of Pennsylvania, Philadelphia, PA; and 4RAND Corporation, Santa Monica, CA.
authors.forename: Kelly R
authors.initials: KR
authors.lastname: Evenson
authors.forename: Fang
authors.initials: F
authors.lastname: Wen
authors.forename: Amy
authors.initials: A
authors.lastname: Hillier
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Cohen
mesh_terms: D061725:Accelerometry; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004777:Environment; D005260:Female; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D011633:Public Facilities / Q000706:statistics & numerical data*; D011998:Recreation; D014481:United States; D055815:Young Adult