title: Insulin secretion and its association with physical activity, fitness and screen time in children.
abstract: OBJECTIVE
  To determine the independent associations of moderate to vigorous physical activity (MVPA), fitness, screen time, and adiposity with insulin secretion in children.
  
  
  METHODS
  Caucasian youth (n = 423/630), 8-10 years old, with at least one obese biological parent, were studied (QUALITY cohort). Insulin secretion was measured using HOMA2-%B, area under the curve (AUC) of insulin to glucose over the first 30 minutes (AUC I/G(t30min)) of the OGTT and AUC I/G(t120min) over 2 hours. Fitness was measured by VO₂peak ; percent fat mass (PFM) by DXA; 7-day MVPA by accelerometry; self-reported screen time included television, video game, or computer use. Models were adjusted for age, sex, season, puberty, PFM, and insulin sensitivity [IS] (HOMA2-IS, Matsuda-ISI).
  
  
  RESULTS
  PFM was strongly associated with insulin secretion, even after adjustment for IS: for every 1% increase in PFM, insulin secretion increased from 0.3% to 0.8% across indices. MVPA was negatively associated with HOMA2-%B (P < 0.05), but not with OGTT-derived measures. Fitness was negatively associated with AUC I/G(t120min) (P < 0.05). Screen time showed a trend toward higher HOMA2-%B in girls (P = 0.060).
  
  
  CONCLUSIONS
  In children with an obese parent, lower insulin secretion is associated with lower adiposity, higher MVPA, better fitness, and possibly reduced screen time.
authors.affiliation: Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montréal, Quebec, Canada; Division of Endocrinology, Department of Pediatrics, CHU Sainte-Justine and Université de Montréal, Montreal, Quebec, Canada; Centre de Recherche du CHU Sainte Justine, Montréal, Quebec, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Henderson
authors.forename: K
authors.initials: K
authors.lastname: Gray-Donald
authors.forename: R
authors.initials: R
authors.lastname: Rabasa-Lhoret
authors.forename: J-P
authors.initials: JP
authors.lastname: Bastard
authors.forename: T A
authors.initials: TA
authors.lastname: Barnett
authors.forename: A
authors.initials: A
authors.lastname: Benedetti
authors.forename: J-P
authors.initials: JP
authors.lastname: Chaput
authors.forename: A
authors.initials: A
authors.lastname: Tremblay
authors.forename: M
authors.initials: M
authors.lastname: Lambert
mesh_terms: D050154:Adiposity; D002648:Child; D002652:Child Behavior; D002657:Child Development; D015331:Cohort Studies; D003201:Computers; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D007333:Insulin Resistance; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D007899:Leisure Activities; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D010101:Oxygen Consumption; D010809:Physical Fitness; D011792:Quebec; D057185:Sedentary Behavior; D013690:Television; D018910:Video Games
chemical_list: D007328:Insulin