title: Use of global positioning system for physical activity research in youth: ESPAÇOS Adolescentes, Brazil.
abstract: The built environment is an important factor associated with physical activity and sedentary behavior (SB) during adolescence. This study presents the methods for objective assessment of context-specific moderate to vigorous physical activity (MVPA) and SB, as well as describes results from the first project using such methodology in adolescents from a developing country. An initial sample of 381 adolescents was recruited from 32 census tracts in Curitiba, Brazil (2013); 80 had their homes geocoded and wore accelerometer and GPS devices for seven days. Four domains were defined as important contexts: home, school, transport and leisure. The majority of participants (n=80) were boys (46; 57.5%), with a normal BMI (52; 65.0%) and a mean age (SD) of 14.5 (5.5) years. Adolescents spent most of their time at home, engaging in SB. Overall, the largest proportion of MVPA was while in transport (17.1% of time spent in this context) and SB while in leisure (188.6min per day). Participants engaged in MVPA for a median of 28.7 (IQR 18.2-43.2) and 17.9 (IQR 9.2-32.1) minutes during week and weekend days, respectively. Participants spent most of their day in the leisure and home domains. The use of Geographic Information System (GIS), Global Positioning System (GPS) and accelerometer data allowed objective identification of the amount of time spent in MVPA and SB in four different domains. Though the combination of objective measures is still an emerging methodology, this is a promising and feasible approach to understanding interactions between people and their environments in developing countries.
authors.affiliation: Graduate Program in Physical Education, Federal University of Parana, Rua Coracao de Maria, 92 Curitiba, Parana, Brazil; Research Group in Physical Activity and Quality of Life (GPAQ), Pontifical Catholic University of Parana, Rua Imaculada Conceicao, 1155 Curitiba, Brazil; Center for Geospatial Analytics, College of Natural Resources, North Carolina State University, 2820 Faucette Drive, 27695 Raleigh, NC, United States; Department of Parks, Recreation and Tourism Management, North Carolina State University, 2820 Faucette Drive, 27695 Raleigh, NC, United States. Electronic address: coalberi@ncsu.edu.
authors.forename: Claudia Oliveira
authors.initials: CO
authors.lastname: Alberico
authors.affiliation: Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark. Electronic address: jschipperijn@health.sdu.dk.
authors.forename: Jasper
authors.initials: J
authors.lastname: Schipperijn
authors.affiliation: Graduate Program in Physical Education, Federal University of Parana, Rua Coracao de Maria, 92 Curitiba, Parana, Brazil; Research Group in Physical Activity and Quality of Life (GPAQ), Pontifical Catholic University of Parana, Rua Imaculada Conceicao, 1155 Curitiba, Brazil; Prevention Research Center, Brown School, Washington University in St. Louis, One Brookings Drive, Campus Box, 1196 St. Louis, United States. Electronic address: reis.rodrigo@wustl.edu.
authors.forename: Rodrigo S
authors.initials: RS
authors.lastname: Reis
mesh_terms: D061725:Accelerometry / Q000379:methods; D000293:Adolescent; D001938:Brazil; D015444:Exercise; D005260:Female; D040362:Geographic Information Systems / Q000706:statistics & numerical data*; D006801:Humans; D007899:Leisure Activities; D008297:Male; D012106:Research; D012574:Schools; D057185:Sedentary Behavior; D057566:Self Report; D014186:Transportation
keywords: Accelerometry; Adolescent; Built environment; Physical activity; Sedentary behavior