Impact of body composition and exercise on food intake regulation in children
Open Access
- Author:
- Fearnbach, Stephanie Nicole
- Graduate Program:
- Nutritional Sciences
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- September 26, 2016
- Committee Members:
- Kathleen Loralee Keller, Dissertation Advisor/Co-Advisor
Kathleen Loralee Keller, Committee Chair/Co-Chair
Barbara Jean Rolls, Committee Member
Rebecca L Corwin, Committee Member
Charles Geier, Outside Member
Danielle Symons Downs, Outside Member
David Thivel, Special Member - Keywords:
- nutrition
exercise
childhood obesity
energy balance
body composition
eating behavior - Abstract:
- Recent childhood obesity prevalence statistics suggest that 17% of children and adolescents ages 2 to 19 years are living with obesity. Determining alternative methods to decrease daily energy intake and increase energy expenditure is critical for childhood obesity prevention. A “one size fits all” approach to treating obesity has not been effective. This dissertation is based on the Energy Balance Framework from Blundell and colleagues, which is a working model that describes the major influences on appetite control. Emerging research is working to better understand the dysregulation of energy balance, with recent studies in adolescents and adults. However, the effects of the energy balance system and appetite regulation pathways on food intake have not been fully examined in younger, pre-adolescent children. This dissertation extends previous research in these areas and examines the influences of individual differences in body composition and exercise on appetite regulation and food intake in children under the age of 12 years, across three separate cohorts of children. In three of the four papers of this dissertation, the role of fat-free mass as an appetitive driver in children emerged as a common theme, consistent with previous work in adults. There was limited evidence of an association between fat mass and food intake across the three cohorts of children studied. Exercise, compared to a sedentary control, was effective in reducing relative energy intake (i.e., energy intake adjusted for activity-related energy expenditure), but individual differences influenced these relationships. Children who rated the controlled bout of exercise as more difficult had greater ad libitum energy intake than children who rated it as easier. This finding demonstrates the potential for perceived exertion during exercise to influence food intake regulation. In addition to this cognitive factor, there may be individual differences in the brain’s reward response to food-related cues that could also play a role in ingestive behavior. Therefore, the work in this dissertation highlights the role of the brain in the determination of energy balance-related behaviors. Collectively, the findings from these studies provide support for the Energy Balance Framework and extend these findings to pre-adolescent children. These three cross-sectional studies represent a few steps towards understanding the influences of body composition and exercise on food intake regulation in children. Additional longitudinal studies in these areas will aid in the understanding of the reciprocal interactions between energy expenditure, energy intake, and body composition over time. These studies may also inform the development of more effective and sustainable tailored weight management interventions.