Responses of Lipolysis to a Meal after Physical Activity in Lean and Obese Children

Purpose: This investigation was conducted to determine whether an acute bout of aerobic exercise would affect lipolytic response to food intake in lean (LN) and obese (OB) children. Methods: 44 children (EX: 16 LN and 28 OB, age 8-11yr) performed 20 min of aerobic exercise eliciting an average heart rate of 140 beats/min (plus 6 min of warm-up and cool-down) between standardized breakfast (~300 kcal) and lunch (~500 kcal) meals, while 21 children (CON: 9 LN and 12 OB, age 8-11 yr) remained rested between meals. Microdialysis probes were inserted into the subcutaneous abdominal adipose tissue to monitor interstitial glycerol (lipolysis). Changes in interstitial glycerol concentrations were calculated from one-hour dialysate samples collected before and after ingestion of each meal. Two-way (meal by adiposity group) ANOVAs were separately performed in EX and CON. Results: In CON, the lipolytic response to the meal was attenuated after lunch compared to after breakfast regardless of obesity status (main effe...