title: Physical activity and clustered cardiovascular risk in children: a cross-sectional study (The European Youth Heart Study).
abstract: BACKGROUND
  Atherosclerosis develops from early childhood; physical activity could positively affect this process. This study's aim was to assess the associations of objectively measured physical activity with clustering of cardiovascular disease risk factors in children and derive guidelines on the basis of this analysis.
  
  
  METHODS
  We did a cross-sectional study of 1732 randomly selected 9-year-old and 15-year-old school children from Denmark, Estonia, and Portugal. Risk factors included in the composite risk factor score (mean of Z scores) were systolic blood pressure, triglyceride, total cholesterol/HDL ratio, insulin resistance, sum of four skinfolds, and aerobic fitness. Individuals with a risk score above 1 SD of the composite variable were defined as being at risk. Physical activity was assessed by accelerometry.
  
  
  RESULTS
  Odds ratios for having clustered risk for ascending quintiles of physical activity (counts per min; cpm) were 3.29 (95% CI 1.96-5.52), 3.13 (1.87-5.25), 2.51 (1.47-4.26), and 2.03 (1.18-3.50), respectively, compared with the most active quintile. The first to the third quintile of physical activity had a raised risk in all analyses. The mean time spent above 2000 cpm in the fourth quintile was 116 min per day in 9-year-old and 88 min per day in 15-year-old children.
  
  
  CONCLUSIONS
  Physical activity levels should be higher than the current international guidelines of at least 1 h per day of physical activity of at least moderate intensity to prevent clustering of cardiovascular disease risk factors.
authors.affiliation: Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway. lars.bo.andersen@nih.no
authors.forename: Lars Bo
authors.initials: LB
authors.lastname: Andersen
authors.forename: Maarike
authors.initials: M
authors.lastname: Harro
authors.forename: Luis B
authors.initials: LB
authors.lastname: Sardinha
authors.forename: Karsten
authors.initials: K
authors.lastname: Froberg
authors.forename: Ulf
authors.initials: U
authors.lastname: Ekelund
authors.forename: Søren
authors.initials: S
authors.lastname: Brage
authors.forename: Sigmund Alfred
authors.initials: SA
authors.lastname: Anderssen
mesh_terms: D000293:Adolescent; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000209:etiology*; D002648:Child; D003430:Cross-Sectional Studies; D005060:Europe; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D010809:Physical Fitness; D012307:Risk Factors