Overview
This study will examine race differences in total energy expenditure and respiratory quotient (RQ) during and after exercise, compared to a sedentary control condition, in adolescent girls who are classified as overweight. In addition, subjective appetite will be measured throughout the assessment periods.
Description
Aim 1: Measure 24-hour energy expenditure and its components (resting, activity, and sleep energy expenditure) and compare differences between African-American and White girls.
Hypothesis: Total, resting, and sleep energy expenditure will be lower in African-American relative to White girls. Activity energy expenditure will be equivalent per the study design.
Aim 2: Measure and compare substrate oxidation and associations with appetite (i.e., hunger, desire to eat) in the context of energy balance between African-American and White girls.
Hypothesis: African-American girls will have a higher RQ at rest, during exercise, and following exercise, and RQ will be positively associated with subjective appetite ratings.
Eligibility
Inclusion Criteria:
- Female
- Age 13-17 years, inclusive
- Achieved menarche based on parent- and/or self-report
- Overweight based on BMI percentile for age and sex ( 85th and < 95th)
- Self-identification as non-Hispanic White or African-American
- Willing to maintain current physical activity, sleep schedule, and dietary habits during the study
- Willing to comply with study procedures
Exclusion Criteria:
- Contraindications to exercise testing as defined by the American College of Sports Medicine (i.e., medical history of cardiovascular, pulmonary, or physical conditions that affect the ability to exercise)
- Food allergies
- Dietary restrictions
- Unwilling to consume study foods
- History of polycystic ovary syndrome (PCOS)
- Current amenorrhea or other menstrual cycle irregularities
- Pregnant or currently breastfeeding
- Current anemia
- Use of medications affecting metabolism or sleep
- Inability to properly or safely complete the study procedures per the investigators' discretion