Insulin secretion and its association with physical activity, fitness and screen time in children

摘要

Objectives To determine the independent associations of moderate to vigorous physical activity (MVPA), fitness, screen time, and adiposity with insulin secretion in children. Design and 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/Gt120min 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.