title: Association between physical activity, participation in Physical Education classes, and social isolation in adolescents.
abstract: OBJECTIVE
  To analyze the association between physical activity, participation in Physical Education classes, and indicators of social isolation among adolescents.
  
  
  METHODS
  This was an epidemiological study based on secondary analysis of data from a representative sample of students (14-19 years) from public high schools (n=4,207). Data were collected through the questionnaire Global School-based Student Health Survey. The independent variables were the level of physical activity and enrollment in Physical Education classes, while the dependent variables were two indicators of social isolation (feeling of loneliness and having few friends). Descriptive and inferential procedures were used in the statistical analysis.
  
  
  RESULTS
  Most of the adolescents were classified as insufficiently active (65.1%) and reported not attending Physical Education classes (64.9%). Approximately two in each ten participants reported feeling of loneliness (15.8%) and, in addition, about one in each five adolescents reported have only one friend (19.5%). In the bivariate analysis, a significantly lower proportion of individuals reporting social isolation was observed among adolescents who referred higher enrollment in Physical Education classes. After adjustment for confounding variables, binary logistic regression showed that attending Physical Education classes was identified as a protective factor in relation to the indicator of social isolation 'having few friends,' but only for girls.
  
  
  CONCLUSIONS
  It was concluded that participation in Physical Education classes is associated with reduced social isolation among female adolescents.
authors.affiliation: Post-graduate Program in Hebiatria, Universidade de Pernambuco (UPE), Camaragibe, PE, Brazil. Electronic address: simonesantosbr@gmail.com.
authors.forename: Simone José dos
authors.initials: SJ
authors.lastname: Santos
authors.affiliation: Post-graduation Program in Physical Education, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brazil; Department of Physical Education, Universidade Federal de Pernambuco (UFPE), Recife, PE, Brazil.
authors.forename: Carla Menêses
authors.initials: CM
authors.lastname: Hardman
authors.affiliation: Post-graduation Program in Physical Education, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brazil; Post-graduation Program in Physical Education, Universidade de Pernambuco (UPE), Recife, PE, Brazil.
authors.forename: Simone Storino Honda
authors.initials: SS
authors.lastname: Barros
authors.forename: Carolina
authors.initials: C
authors.lastname: Santos da Franca
authors.affiliation: Post-graduate Program in Hebiatria, Universidade de Pernambuco (UPE), Camaragibe, PE, Brazil.
authors.forename: Carolina da F B F
authors.initials: Cda F
authors.lastname: Santos
authors.affiliation: Post-graduate Program in Hebiatria, Universidade de Pernambuco (UPE), Camaragibe, PE, Brazil; Post-graduation Program in Physical Education, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brazil; Post-graduation Program in Physical Education, Universidade de Pernambuco (UPE), Recife, PE, Brazil.
authors.forename: Mauro Virgilio Gomes de
authors.initials: MV
authors.lastname: Barros
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity; D010806:Physical Education and Training / Q000706:statistics & numerical data*; D012934:Social Isolation / Q000523:psychology*; D013334:Students / Q000523:psychology* / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Adolescent; Adolescente; Amigos; Atividade física; Educação física; Friends; Isolamento social; Physical Education; Physical activity; Social isolation