title: Correlates of objectively measured physical activity in adults and older people: a cross-sectional study of population-based sample of adults and older people living in Norway.
abstract: OBJECTIVE
  The aims of the study were to identify correlates of objectively measured physical activity and to determine whether the explanatory power of the correlates differed with sex, weight status or level of education.
  
  
  METHODS
  Physical activity was assessed objectively in 3,867 participants, aged 20-85 years, for a consecutive 7 days using the ActiGraph GT1M activity monitor. Demographic and biological variables and levels of psychological, social environmental and physical environmental correlates were self-reported.
  
  
  RESULTS
  The complete set of correlates explained 18.6 % (p < 0.001) of the variance in overall physical activity. Age and physical activity identity were the most important factors, explaining 4.8 and 3.2 % of the variance, respectively, whereas social environmental and physical environmental correlates did not significantly increase the amount of explained variance. Small interaction effects between demographic and biological variables and the correlates were observed.
  
  
  CONCLUSIONS
  Self-efficacy, perceived behavioural control and physical activity identity might be important targets for intervention. Intervention efforts aimed at influencing psychological correlates of physical activity may prove equally effective regardless of sex, weight status and level of education.
authors.affiliation: Department of Sports Medicine, Norwegian School of Sport Sciences, Ullevaal Stadion, P.O. Box 4014, 0806, Oslo, Norway, bjorge.herman.hansen@nih.no.
authors.forename: Bjørge Herman
authors.initials: BH
authors.lastname: Hansen
authors.forename: Yngvar
authors.initials: Y
authors.lastname: Ommundsen
authors.forename: Ingar
authors.initials: I
authors.lastname: Holme
authors.forename: Elin
authors.initials: E
authors.lastname: Kolle
authors.forename: Sigmund Alfred
authors.initials: SA
authors.lastname: Anderssen
mesh_terms: D056044:Actigraphy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004522:Educational Status; D015444:Exercise / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009664:Norway; D011634:Public Health; D020377:Self Efficacy; D055815:Young Adult