title: Physical Activity Awareness of British Adolescents.
abstract: OBJECTIVE
  To assess adolescent PA awareness and investigate associations with biological and psychosocial factors.
  
  
  METHODS
  Cross-sectional from November 2005 to July 2007 (ROOTS study).
  
  
  METHODS
  Population-based sample recruited via Cambridgeshire and Suffolk schools (UK).
  
  
  METHODS
  N=799 (44% male, 14.5±0.5 years).
  
  
  METHODS
  Self-rated PA perception, self-reported psychosocial factors, measured anthropometry.
  
  
  METHODS
  PA measured using accelerometry over five days. 'Inactive' defined as accelerometry-measured <60 min/day of at least moderate PA (MVPA). Associations between awareness (agreement between self-rated and accelerometry-measured active/inactive) and potential correlates investigated using multinomial logistic regression.
  
  
  RESULTS
  70% of adolescents were inactive (81% of girls, 56% of boys, OR(95% CI) 3.41(2.41, 4.82)). 53% of all girls (63% of inactive girls) and 34% of all boys (60% of inactive boys) inaccurately rated themselves as active (over-estimators). Compared to girls accurately describing themselves as inactive (29%), girl over-estimators had lower fat mass (OR(95% CI) 0.84(0.70, 0.99)), higher SES (high vs. low 2.4(1.07, 5.32)), reported more parent-support (1.57(1.12, 2.22)) and better family relationships (0.25(0.09, 0.67)). Amongst boys accurately describing themselves as inactive (22%), over-estimators had lower fat mass (0.86(0.77, 0.96)) reported more peer-support (1.75(1.32, 2.30)) and less teasing (0.75(0.61, 0.92)).
  
  
  CONCLUSIONS
  A substantial number of adolescents believe themselves to be more physically active than they really are. They maybe unaware of potential health risks, and may be unlikely to participate in PA promotion programs. Increasing information of PA health benefits beyond weight control might help encourage behavior change.
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Corder
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Esther Mf
authors.initials: EM
authors.lastname: van Sluijs
authors.affiliation: Developmental Psychiatry Section, Department of Psychiatry, University of Cambridge, Douglas House, 18b Trumpington Road, Cambridge, CB2 8AH, U.K.
authors.forename: Ian
authors.initials: I
authors.lastname: Goodyer
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Charlotte L
authors.initials: CL
authors.lastname: Ridgway
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Rebekah M
authors.initials: RM
authors.lastname: Steele
authors.affiliation: Developmental Psychiatry Section, Department of Psychiatry, University of Cambridge, Douglas House, 18b Trumpington Road, Cambridge, CB2 8AH, U.K.
authors.forename: Diane
authors.initials: D
authors.lastname: Bamber
authors.affiliation: Developmental Psychiatry Section, Department of Psychiatry, University of Cambridge, Douglas House, 18b Trumpington Road, Cambridge, CB2 8AH, U.K.
authors.forename: Valerie
authors.initials: V
authors.lastname: Dunn
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Griffin
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, Box 285 Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, U.K.
authors.forename: Ulf
authors.initials: U
authors.lastname: Ekelund
keywords: Physical activity; awareness; correlates; perception; psychosocial