title: Perceived Exertion during Exercise Is Associated with Children's Energy Intake.
abstract: To examine the individual-level factors that predict energy intake (EI) after imposed exercise (EX) and sedentary time (SED) in children.
  
  
  
  Healthy-weight children ages 9-12 yr (n = 20) reported to the laboratory for one baseline and two experimental visits (EX and SED) each separated by 1 wk in a randomized crossover design. Percent body fat, weight (kg), and height (m) were used to calculate fat-mass index (FM index) and fat-free mass index (FFM index; kg·m). On the EX day, children exercised at 70% estimated V˙O2peak for 30 min on a cycle ergometer, whereas cardiovascular responses and RPE were measured. Objective EI (kcal) was measured at identical meals (breakfast, lunch, snack, and dinner) on the EX and SED days.
  
  
  
  Total EI was not statistically different between the EX and SED days (t = 1.8, P = 0.09). FFM index was positively associated with EI on the EX day (r = 0.54, P < 0.05). RPE was also positively associated with EI on the EX day (r = 0.82, P < 0.001). Together, FFM index and RPE explained 77% of the variability in EX day EI (F(2,17) = 26.4, P < 0.001). For each unit increase in RPE, children consumed approximately 270 more calories on the EX day. A similar pattern of associations was observed on the SED day.
  
  
  
  FFM index was positively associated with EI on the EX day. Despite experiencing the same 70% relative exercise intensity, increased perceived difficulty predicted greater EI on both the EX and SED day. These findings demonstrate a role for both FFM and RPE in explaining EI variability in children.
authors.affiliation: 1Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA; 2Department of Human Development and Family Studies, The Pennsylvania State University, University Park, PA; 3Department of Educational Psychology, University of Connecticut, Storrs, CT; 4Department of Kinesiology, The Pennsylvania State University, University Park, PA; 5Laboratory of the Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), Clermont Auvergne University, Clermont-Ferrand, FRANCE; 6CRNH-Auvergne, Clermont-Ferrand, FRANCE; and 7Department of Food Science, The Pennsylvania State University, University Park, PA.
authors.forename: S Nicole
authors.initials: SN
authors.lastname: Fearnbach
authors.forename: Travis D
authors.initials: TD
authors.lastname: Masterson
authors.forename: Haley A
authors.initials: HA
authors.lastname: Schlechter
authors.forename: Eric
authors.initials: E
authors.lastname: Loken
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Downs
authors.forename: David
authors.initials: D
authors.lastname: Thivel
authors.forename: Kathleen L
authors.initials: KL
authors.lastname: Keller
mesh_terms: D061725:Accelerometry; D000886:Anthropometry; D050218:Body Fat Distribution; D002648:Child; D018592:Cross-Over Studies; D004435:Eating; D015444:Exercise / Q000502:physiology / Q000523:psychology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D010465:Perception; D005082:Physical Exertion; D057185:Sedentary Behavior