title: The relationships between body mass index and television viewing, internet use and cellular phone use: the moderating effects of socio-demographic characteristics and exercise.
abstract: OBJECTIVE
  This study aimed to examine the relationships between body mass index (BMI) and television viewing, Internet use and cellular phone use and the moderators for these relationships in adolescents.
  
  
  METHODS
  The relationship between BMI and the time spent on three kinds of sedentary activities and the moderators for these relationships were analyzed among 9,278 Taiwanese adolescents. The different relationships between BMI and various Internet and cellular phone-related activities were analyzed.
  
  
  RESULTS
  High television viewing and high Internet use were associated with increased BMI in adolescents. Exercising had a moderating effect on the relationship between BMI and television viewing. Several Internet and cellular phone-related activities were associated with increased BMI.
  
  
  CONCLUSIONS
  The results support the relationships between adolescent BMI and television viewing and Internet use. The moderating effect of exercise and various Internet and cellular phone-related activities should be considered when developing intervention strategies for overweight adolescents.
authors.affiliation: Department of Psychiatry, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Cheng-Fang
authors.initials: CF
authors.lastname: Yen
authors.forename: Ray C
authors.initials: RC
authors.lastname: Hsiao
authors.forename: Chih-Hung
authors.initials: CH
authors.lastname: Ko
authors.forename: Ju-Yu
authors.initials: JY
authors.lastname: Yen
authors.forename: Chi-Fen
authors.initials: CF
authors.lastname: Huang
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Liu
authors.forename: Shing-Yaw
authors.initials: SY
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D040421:Cell Phone / Q000706:statistics & numerical data*; D015444:Exercise; D005260:Female; D006306:Health Surveys; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D008019:Life Style; D008297:Male; D009765:Obesity; D050177:Overweight; D012044:Regression Analysis; D012923:Social Class; D011795:Surveys and Questionnaires; D013624:Taiwan; D013690:Television / Q000706:statistics & numerical data*