title: Sex differences in exercise behavior during adolescence: is biological maturation a confounding factor?
abstract: OBJECTIVE
  To test the hypothesis that sex-related differences in exercise behavior during adolescence are confounded by biological age.
  
  
  METHODS
  Biological age and leisure-time exercise activity were assessed in 103 male and 83 female British Year 9 students (mean = 14.04 years, SD = 0.31). To assess exercise behavior, participants completed the Leisure-Time Exercise Questionnaire (LTEQ). Percentage of predicted adult height attained at measurement was used as an estimate of biological maturity status. Males reported more frequent engagement in strenuous forms of exercise and total exercise activity than females.
  
  
  RESULTS
  Sex differences in exercise behavior were attenuated and nonsignificant when biological maturity was controlled for.
  
  
  CONCLUSIONS
  Sex-related differences in biological maturity contribute to sex-related differences in exercise behavior during adolescence.
authors.affiliation: School for Health, University of Bath, Bath, United Kingdom. S.Cumming@bath.ac.uk
authors.forename: Sean P
authors.initials: SP
authors.lastname: Cumming
authors.forename: Martyn
authors.initials: M
authors.lastname: Standage
authors.forename: Fiona
authors.initials: F
authors.lastname: Gillison
authors.forename: Robert M
authors.initials: RM
authors.lastname: Malina
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D041923:Adolescent Development / Q000502:physiology*; D015992:Body Mass Index; D015986:Confounding Factors, Epidemiologic; D004739:England; D015444:Exercise / Q000502:physiology* / Q000523:psychology; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008297:Male; D010806:Physical Education and Training; D010809:Physical Fitness; D012737:Sex Factors; D012741:Sexual Maturation / Q000502:physiology; D011795:Surveys and Questionnaires