title: Preschool physical activity and functional constipation: the Generation R study.
abstract: OBJECTIVE
  Decreased physical activity levels in children may partly explain the rising prevalence of functional constipation in childhood. The aim of the present study, therefore, was to examine the association between physical activity and functional constipation during the preschool period.
  
  
  METHODS
  This study was embedded in the Generation R study, a large prospective birth-cohort study in Rotterdam, The Netherlands. Physical activity was measured by an Actigraph accelerometer in 347 children (182 boys, 165 girls; mean age 25.1 months) and data were expressed as counts per minute. Data were categorized into light activity (302-614 counts/15 seconds), moderate activity (615-1230 counts/15 seconds), and vigorous activity (≥1231 counts/15 seconds). Functional constipation in the third and fourth year of life was defined according to the Rome II criteria.
  
  
  RESULTS
  Children spending time in the highest tertile of light (adjusted odds ratio [OR] 0.34; 95% confidence interval [CI] 0.13-0.87), moderate (adjusted OR 0.37; 95% CI 0.14-0.97), and total activity (adjusted OR 0.37; 95% CI 0.15-0.92) at the age of 2 years had significantly less functional constipation in the fourth year of life. For functional constipation in the third year of life, the results were in similar direction but not statistically significant. Additionally, children with physical activity of more than the WHO recommendation of 60 min/day had significantly less functional constipation in the fourth year of life (adjusted OR 0.48; 95% CI 0.24-0.97).
  
  
  CONCLUSIONS
  Physical activity is associated with a decreased risk of functional constipation in the preschool period, but this may be time dependent.
authors.affiliation: *Department of Pediatrics †Department of Public Health ‡Department of Epidemiology, Erasmus Medical Center, Rotterdam §Department of Healthy Living, Expertise Centre Life Style TNO, Leiden (SIdV), The Netherlands.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Driessen
authors.forename: Jessica C
authors.initials: JC
authors.lastname: Kiefte-de Jong
authors.forename: Anne
authors.initials: A
authors.lastname: Wijtzes
authors.forename: Sanne I
authors.initials: SI
authors.lastname: de Vries
authors.forename: Vincent W V
authors.initials: VW
authors.lastname: Jaddoe
authors.forename: Albert
authors.initials: A
authors.lastname: Hofman
authors.forename: Hein
authors.initials: H
authors.lastname: Raat
authors.forename: Henriette A
authors.initials: HA
authors.lastname: Moll
mesh_terms: D056044:Actigraphy; D000328:Adult; D002675:Child, Preschool; D003109:Colonic Diseases, Functional / Q000209:etiology / Q000517:prevention & control*; D003248:Constipation / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D012574:Schools; D057185:Sedentary Behavior