title: The fractionalization of physical activity throughout the week is associated with the cardiometabolic health of children and youth.
abstract: BACKGROUND
  The influence of the fractionalization of moderate- to vigorous- intensity physical activity (MVPA) throughout the week on the health of children is unknown. We compared cardiometabolic risk factors in physically active children who accumulated their weekly MVPA in different patterns.
  
  
  METHODS
  We studied 745 participants aged 6-19 years. MVPA was measured using accelerometers over 7 days. Three groups were created: Insufficiently Active, <60 minutes/day of MVPA on average; Infrequently Active, ≥60 minutes/day of MVPA on average but exceeding the 60 minute target <5 days; and Frequently Active, ≥60 minutes/day MVPA on average and exceeding the 60 minute target ≥5 days. Percentile scores for 8 cardiometabolic risk factors were determined.
  
  
  RESULTS
  The least favorable cardiometabolic risk factor profile was observed in the Insufficiently Active group. The Frequently Active group had more favorable (5-6 percentile unit difference) diastolic blood pressure, HDL-cholesterol, insulin resistance, and metabolic syndrome scores than the Infrequently Active group, although only the difference for insulin resistance was statistically significant (P < 0.05). These differences remained after controlling for the weekly volume of MVPA.
  
  
  CONCLUSIONS
  The fractionalization of MVPA throughout the week was associated with insulin resistance.
authors.affiliation: Department of Public Health Sciences, School of Kinesiology and Health Studies, Queen's University, Kingston, ON, Canada. ian.janssen@queensu.ca
authors.forename: Ian
authors.initials: I
authors.lastname: Janssen
authors.forename: Suzy L
authors.initials: SL
authors.lastname: Wong
authors.forename: Rachel
authors.initials: R
authors.lastname: Colley
authors.forename: Mark S
authors.initials: MS
authors.lastname: Tremblay
mesh_terms: D061725:Accelerometry; D000293:Adolescent; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000097:blood / Q000175:diagnosis*; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008659:Metabolic Diseases / Q000097:blood / Q000175:diagnosis*; D024821:Metabolic Syndrome / Q000175:diagnosis; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000175:diagnosis*; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D008076:Cholesterol, HDL