title: Objectively measured physical activity in children from a southern Brazilian city: a population-based study.
abstract: BACKGROUND
  The aim of this study was to assess physical activity (PA) patterns (intensity and prevalence) in children according to demographic, socioeconomic, and familiar characteristics.
  
  
  METHODS
  In 2010, a cross-sectional study of 239 children aged 4-11 was conducted, in Pelotas, Southern Brazil. PA was measured by accelerometry and classified in different intensities. Insufficient physical activity was defined as less than 60 min/day of moderate-to-vigorous PA. Descriptive analyses of accelerometry-related variables were presented. Multivariate Poisson regression models were used to estimate the association between physical insufficient PA and covariates.
  
  
  RESULTS
  For both sexes, around 65% of the registered time was spent in sedentary activities and less than 20 min/day in vigorous activity. Age and economic status were inversely associated to PA in all categories of PA. Moderate and vigorous activities means were higher in boys than in girls. The prevalence of insufficient PA was 34.5% in girls and 19.5% in boys.
  
  
  CONCLUSIONS
  We found important differences in physical activity patterns according to sex and economic status, as well as a significant decline in time spent in moderate-to-vigorous PA with increasing age. Understanding the relationship between these sociodemographic factors is important to tackle low levels of PA.
authors.affiliation: post-graduate program in Epidemiology, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil.
authors.forename: Renata Moraes
authors.initials: RM
authors.lastname: Bielemann
authors.forename: Andreia Morales
authors.initials: AM
authors.lastname: Cascaes
authors.forename: Felipe Fossati
authors.initials: FF
authors.lastname: Reichert
authors.forename: Marlos R
authors.initials: MR
authors.lastname: Domingues
authors.forename: Denise Petrucci
authors.initials: DP
authors.lastname: Gigante
mesh_terms: D061725:Accelerometry / Q000706:statistics & numerical data*; D056044:Actigraphy / Q000706:statistics & numerical data*; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D007899:Leisure Activities; D008297:Male; D009043:Motor Activity; D015999:Multivariate Analysis; D011159:Population Surveillance; D015995:Prevalence; D012111:Residence Characteristics; D012959:Socioeconomic Factors