title: Is physical activity differentially associated with different types of sedentary pursuits?
abstract: OBJECTIVE
  To determine whether there is a relationship between the time adolescents spend in physical activity and time they spend in different sedentary pursuits: watching television, playing video games, working on computers, doing homework, and reading, taking into account the effect of part-time work on students' residual time.
  
  
  METHODS
  Cross-sectional cohort design.
  
  
  METHODS
  Seven hundred forty-three high school students from 2 inner-city public schools and 1 private school.
  
  
  METHODS
  Students completed a self-administered questionnaire that addressed time spent in physical activity, time spent in sedentary pursuits, musculoskeletal pain, and psychosocial issues and were also measured for height and weight. Main Outcome Measure Level of physical activity (low, moderate, high).
  
  
  RESULTS
  There were more girls than boys in the low and moderate physical activity groups and more boys than girls in the high activity group. Ordinal logistic regression showed that increased time spent in "productive sedentary behavior" (reading or doing homework and working on computers) was associated with increased physical activity (odds ratio, 1.7; 95% confidence interval, 1.2-2.4), as was time spent working (odds ratio, 1.3; 95% confidence interval, 1.2-1.4). Time spent watching television and playing video games was not associated with decreased physical activity.
  
  
  CONCLUSIONS
  Physical activity was not inversely associated with watching television or playing video games, but was positively associated with productive sedentary behavior and part-time work. Some students appear capable of managing their time better than others. Future studies should explore the ability of students to manage their time and also determine what characteristics are conducive to better time management.
authors.affiliation: Groupe de recherche interdisciplinaire en santé, Ecole de Réadaptation, Université de Montréal, Montréal, Québec, Canada. Debbie.Feldman@umontreal.ca
authors.forename: Debbie Ehrmann
authors.initials: DE
authors.lastname: Feldman
authors.forename: Tracie
authors.initials: T
authors.lastname: Barnett
authors.forename: Ian
authors.initials: I
authors.lastname: Shrier
authors.forename: Michel
authors.initials: M
authors.lastname: Rossignol
authors.forename: Lucien
authors.initials: L
authors.lastname: Abenhaim
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D002170:Canada; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004526:Efficiency; D004651:Employment; D005260:Female; D015438:Health Behavior; D006801:Humans; D007899:Leisure Activities; D016015:Logistic Models; D008297:Male; D009043:Motor Activity; D015999:Multivariate Analysis; D009140:Musculoskeletal Diseases / Q000503:physiopathology; D010146:Pain / Q000503:physiopathology / Q000523:psychology; D012044:Regression Analysis; D012574:Schools / Q000145:classification; D012737:Sex Factors; D011795:Surveys and Questionnaires