Overweight Adolescents
Conditions
Keywords
Energy expenditure, Substrate oxidation, Appetite, Exercise, Energy intake
Brief summary
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 and objective energy intake will be measured throughout the assessment periods.
Detailed 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) and energy intake 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 and energy intake.
Interventions
OTHERAcute exercise
Participants will complete a morning exercise bout at 70% of their individual maximal aerobic capacity to burn 200 kilocalories above their basal metabolic rate.
Sponsors
Nutrition Obesity Research Center
Pennington Biomedical Research Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
Within-subjects crossover design. The order of conditions is counterbalanced within each subgroup of participants.
Eligibility
Sex/Gender
FEMALE
Age
13 Years to 17 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Exercise Day Energy expenditure | 24 hours on Exercise Day | Total energy expenditure and its components (sleeping, wake \[non-exercise\], activity) as measured by the metabolic chamber |
| Sedentary Day Substrate oxidation | 24 hours on Sedentary Day | Non-protein respiratory quotient (i.e., carbohydrate and fat utilization) as measured by the metabolic chamber |
| Exercise Day Substrate oxidation | 24 hours on Exercise Day | Non-protein respiratory quotient (i.e., carbohydrate and fat utilization) as measured by the metabolic chamber |
| Sedentary Day Energy expenditure | 24 hours on Sedentary Day | Total energy expenditure and its components (sleeping, wake \[non-exercise\], activity) as measured by the metabolic chamber |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Exercise Day Appetite | 24 hours on Exercise Day | Overall subjective appetite and its components (hunger, fullness, desire to eat, prospective food consumption, satisfaction, food wanting) assessed by visual analog scales (0-100 mm) during the metabolic chamber assessments |
| Sedentary Day Appetite | 24 hours on Sedentary Day | Overall subjective appetite and its components (hunger, fullness, desire to eat, prospective food consumption, satisfaction, food wanting) assessed by visual analog scales (0-100 mm) during the metabolic chamber assessments |
| Exercise Day Energy Intake | 24 hours on Exercise Day | Objectively measured food intake during the metabolic chamber assessments will be converted to energy intake in kilocalories |
| Sedentary Day Energy Intake | 24 hours on Sedentary Day | Objectively measured food intake during the metabolic chamber assessments will be converted to energy intake in kilocalories |
Other
| Measure | Time frame | Description |
|---|---|---|
| Implicit activity preferences | Baseline screening visit | Relative preference for physical versus sedentary activities as assessed by a forced-choice behavioral task |
| Body shape | Baseline screening visit | 3D optical imaging assessment of body shape by Fit3D scanner |
| Dual-energy x-ray absorptiometry (DXA) | Baseline screening visit | Total body composition (fat, muscle, bone tissue) measured by Hologic Discovery DXA |
| Habitual physical activity | 7 days leading up to Exercise Day and Sedentary Day | Accelerometry measures of usual physical activity before each experimental visit |
| Cardiorespiratory fitness | Baseline screening visit | Maximal aerobic capacity assessed by graded cycle ergometer test to volitional fatigue |
| Resting metabolic rate | Baseline screening visit | Measured over a 30-minute period by ventilated hood and metabolic cart |
| Habitual sedentary time | 7 days leading up to Exercise Day and Sedentary Day | Accelerometry measures of usual sedentary time before each experimental visit |
| Habitual food intake | 3 days leading up to Exercise Day and Sedentary Day | Food intake diary/dietary record to assist participants in maintaining consistent diet before each experimental visit |
Countries
United States
Outcome results
None listed