title: Joint use policies: are they related to adolescent behavior?
abstract: OBJECTIVE
  Joint use policies (JUP) encourage shared facility use, usually between schools and a city or private organization, for both physical activity-related and non-physical activity-related programs. Little is known about JUP's impact on physical activity (PA). This study examined whether more specific JUPs were associated with increased PA and decreased sedentary behavior (SB) in adolescents.
  
  
  METHODS
  Data on PA, sports participation, and SB were taken from annual cross-sectional nationally representative samples of 51,269 8th, 10th and 12th grade public school students nested in 461 school districts in the US from 2009-2011. JUP measures were constructed using information obtained from corresponding school district JU policies. Multivariable analyses were conducted, controlling for individual demographic and socioeconomic characteristics and clustering at the district level.
  
  
  RESULTS
  Results showed small associations between more specific JUPs and increased PA (IRR 1.01, 95% CI: 1.00, 1.02). Closer examination of specific JUP provisions indicates that specifying what times facilities are available for use was associated with vigorous exercise and prioritizing school or affiliated organizations' use and which spaces were available for use were associated with vigorous exercise and more frequent PA participation, which includes participation in sports or athletics. No associations were found between more specific JUPs and SB.
  
  
  CONCLUSIONS
  JUPS may have small influences on adolescent physical activity behavior. Future longitudinal studies should be conducted to examine the impact of JUPs in conjunction with other physical activity-related policies and environmental changes to determine what impact they have on overall adolescent physical activity and sedentary behavior.
authors.affiliation: University of Illinois at Chicago, Institute for Health Research and Policy and Department of Health Policy & Administration, School of Public Health, 1747W. Roosevelt Road, M/C 275, Room 558, Chicago, IL 60608, USA. Electronic address: sslater@uic.edu.
authors.forename: Sandy
authors.initials: S
authors.lastname: Slater
authors.affiliation: University of Illinois at Chicago, Institute for Health Research and Policy, 1747W. Roosevelt Road, M/C 275, Room 558, Chicago, IL 60608, USA. Electronic address: jchriqui@uic.edu.
authors.forename: Jamie
authors.initials: J
authors.lastname: Chriqui
authors.affiliation: University of Illinois at Chicago, Institute for Health Research and Policy and Department of Economics, 1747W. Roosevelt Road, M/C 275, Room 558, Chicago, IL 60608, USA. Electronic address: fjc@uic.edu.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Chaloupka
authors.affiliation: University of Michigan Institute for Social Research, 426 Thompson St., Ann Arbor, MI 48106-1248, USA. Electronic address: lloyd@umich.edu.
authors.forename: Lloyd
authors.initials: L
authors.lastname: Johnston
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans; D007373:Interinstitutional Relations; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009939:Organizations, Nonprofit; D057766:Policy; D012044:Regression Analysis; D012574:Schools; D057185:Sedentary Behavior; D013334:Students; D011795:Surveys and Questionnaires; D014481:United States
keywords: Adolescents; Joint use policies; Physical activity; Sedentary behavior