Location: Children's Nutrition Research Center
Project Number: 3092-10700-068-003-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Apr 1, 2024
End Date: Mar 31, 2029
Objective:
Objective 1: Examine the role of sedentary behaviors in children’s energy expenditure and risk of overweight or obesity.
Sub-objective 1.A: Quantify the EE of several different types of sedentary behaviors, including use of different types of screen media platforms, among children 3-5 years old.
Sub-objective 1.B: Assess whether children’s usual screen use is associated with the EE of different sedentary screen use activities among 3-5 year-olds.
Objective 2: Determine the impact of sleep and circadian health on children’s energy expenditure and risk of overweight or obesity.
Sub-objective 2.A: Examine the association between children’s usual sleep duration and children’s EE during various types of sedentary activities.
Sub-Objective 2.B: Examine the association between markers of circadian health (e.g., later sleep midpoint, circadian phase, and Entrainment Signal Regularity Index and children’s EE during various types of sedentary activities.
Sub-Objective 2.C: Validate methods for estimating sleep using wearable devices among pediatric populations.
Objective 3: Characterize the role of sleep timing and quality on bone quality and strength in children.
Sub-objective 3.A: Characterize the relationship of habitual sleep and chronotype with bone density, microarchitecture and strength in adolescent youth with overweight compared with normal weight peers while accounting for important covariates (sex and race-ethnicity), and confounders (dietary intake and PA).
Sub-objective 3.B: Determine the relationship of sleep measures to circulating biomarkers of bone formation and resorption, and the mediating effects of insulin resistance, inflammation, cortisol and catecholamines, after adjustment for relevant covariates of diet, body composition, sex, and race-ethnicity.
Objective 4: Examine the impact of patterns and characteristics of 24-hour activity and sleep behaviors on type-2 diabetes related outcomes.
Sub-objective 4.A: Investigate patterns and characteristics of 24-hour activity and sleep cycles and their associations with T2D related outcomes (adiposity, energy expenditure, insulin resistance, HbA1c).
Sub-objective 4.B: Examine the impact of changes in patterns and characteristics of 24-hour activity and sleep behaviors on T2D-related outcomes (adiposity, insulin resistance, HbA1c).
Objective 5: Determine the effect of increasing physical activity and stopping evening snacking on metabolic health, gene expression and fasting plasma amino acid concentrations.
Sub-objective 5.A: Determine the effect of increasing PA in combination with omitting evening snacking on insulin sensitivity for glucose and fat disposal, body composition, TEE, and other significant metabolic biomarkers in adolescents with prediabetes.
Sub-objective 5.B: Identify the effect of increasing PA and omitting evening snacking on gene expression levels modulating insulin signaling, inflammation, and appetite in adolescents with prediabetes.
Sub-objective 5.C: Determine the effect of increasing PA and omitting evening snacking on dysregulated fasting plasma amino acid concentrations.
Approach:
Energy expenditure (EE) in children is influenced by their physical activity (PA), sedentary time, duration and quality of sleep, and circadian rhythms, which affect their adiposity and metabolic health. The relationship between television (TV) viewing and adiposity is not well understood. The mechanisms underlying the relationship between sleep, circadian stability, and body mass index are unclear, though the impact on daytime resting EE during screen use is a potential mechanism that has yet to be examined. Sleep dysfunction can also interfere with energy metabolism in children and studies suggest that short sleep duration and sleep dysfunction negatively impact bone metabolism, yet, the underlying mechanisms remain undefined. The interaction between sleep and adiposity on bone health is also not clear. Lastly, low levels of PA, excessive time in sedentary behaviors, and shorter sleep durations increase the risk of youth-onset type 2 diabetes (T2D). Rigorous studies of children’s PA, sedentary time, and/or sleep will be conducted in four different samples: 1) diverse healthy preschool aged children, 2) diverse adolescents with or without obesity, 3) Hispanic adolescents at risk for T2D, and 4) diverse adolescents with pre-diabetes to examine the mechanism(s) for which PA, sedentary time, and/or sleep influence children’s risk of obesity, bone and/or metabolic health to address five objectives. Findings will help inform intervention, prevention, and guidelines to promote better metabolic health among youth.
