Location: Healthy Body Weight Research
Project Number: 3062-51000-049-00-D
Project Type: Appropriated
Start Date: Apr 21, 2011
End Date: Sep 30, 2014
Objective 1: Develop and validate assessments of behavioral factors that influence energy intake by a) development and validation of a satiety index of foods that reflects interactions of food with physical activity, body mass index, gender, and age; and b) determination of the effect of exercise on energy intake and eating rate. Objective 2: Develop methods for assessing patterns of energy expenditure that include a) validation of breath markers as indicators of energy substrate utilization and; b) characterization of seasonal patterns of energy expenditure and balance in free-living individuals using novel applications of existing technologies (e.g., GPS, accelerometry, heart rate monitoring, doubly labeled water).
To complete the objectives of this proposal, we will conduct a series of studies with human volunteers. For Objective 1, we will model the satiating effects of selected individual food items and mixed meals. Our model will include the comparisons of hormonal and metabolic responses to food consumption to subjective satiety responses and subsequent energy intake, which we will evaluate in a repeated measures design human trial. In Objective 2a, we will conduct controlled feeding studies to determine the effects of caloric restriction and exercise on breath markers of substrate utilization. In Objective 2b, we will identify seasonal changes in body fat, as well as where, how much, and when physical activity and dietary intake vary seasonally.