The purpose of this study is to determine the effect of severe obesity on physical activity, sedentary behavior and cardiometabolic risk factors during childhood and adolescence and whether these associations are modified by race. Additionally, the study will investigate the contributions of (total, regional, and depot-specific) fat accumulation on changes in physical activity, sedentary behavior, and cardiometabolic risk factors during childhood and adolescence.
The proposed study will establish a prospective pediatric cohort to identify intervention targets based on the location, timing, barriers, and facilitators of current physical activity and sedentary behavior in a child's day. The project will be a prospective examination of 340 African American and White girls and boys aged 10 to 16 years, including 50% who are classified as severely obese. State-of-the-art technology will be used including accelerometry to quantify physical activity, magnetic resonance imaging to quantify fat accumulation, and geographic position system and ecological momentary assessment to identify environmental and socio-emotional barriers and facilitators. In further detail, this study will examine the following objectives: Objective 1: Determine the effect of severe obesity on physical activity, sedentary behavior, and cardiometabolic risk factors during childhood and adolescence and whether these associations are modified by race. Objective 2: Investigate the contribution of (total, regional, and depot-specific) fat accumulation on changes in physical activity, sedentary behavior, and cardiometabolic risk factors during childhood and adolescence. Objective 3: Determine barriers and facilitators of physical activity that are related to obesity, including environmental and socio-emotional factors.
Study Type
OBSERVATIONAL
Enrollment
342
Pennington Biomedical Research Center
Baton Rouge, Louisiana, United States
Objective 1 Primary Outcome: Change in Minutes of Sedentary Behavior, Light Physical Activity, and Moderate-to-vigorous Physical Activity
Physical activity and sedentary behavior will be measured by a triaxial accelerometer (Actigraph GT3X+, Actigraph of Ft. Walton Beach, FL). The participant will be instructed to wear the accelerometer on an elasticized belt, on the left mid-axillary line. The Actigraph is one of the most common accelerometers used for scientific purposes. Participants will be encouraged to wear the accelerometer 24-hours per day for at least 7-days (plus an initial familiarization day and the morning of the final day), including 2 weekend days. Participants will also complete a Lifestyle survey to collect information including diet and physical activity habits.
Time frame: Baseline and Year 2
Objective 2 Primary Outcome: Relationship Between Total Fat Accumulation and Change in Sedentary Behavior - Visceral Adipose Tissue
Body composition will be determined by DXA and MRI. With DXA, total body fat and trunk fat will be measured by whole-body DXA using a GE iDXA scanner (GE Medical Systems, Milwaukee, WI) to quantify total and regional body fat (including trunk fat). MRI - Visceral fat, i.e. visceral adipose tissue, will be measured by water-fat shifting MRI using the General Electric Discovery 750w 3.0 Tesla (GE Medical Systems, Milwaukee, WI). IDEAL-IQ imaging technique will be used to generate water-only, fat-only, in-phase, and out-of-phase echoes in a single acquisition with a 20-second breath-hold. Sedentary behavior will be measured by a a triaxial accelerometer as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2
Objective 2 Primary Outcome: Relationship Between Total Fat Accumulation and Change in Sedentary Behavior - Adiposity
Body composition will be determined by DXA and MRI. With DXA, total body fat and trunk fat will be measured by whole-body DXA using a GE iDXA scanner (GE Medical Systems, Milwaukee, WI) to quantify total and regional body fat (including trunk fat). MRI - Visceral fat, i.e. visceral adipose tissue, will be measured by water-fat shifting MRI using the General Electric Discovery 750w 3.0 Tesla (GE Medical Systems, Milwaukee, WI). IDEAL-IQ imaging technique will be used to generate water-only, fat-only, in-phase, and out-of-phase echoes in a single acquisition with a 20-second breath-hold. Sedentary behavior will be measured by a a triaxial accelerometer as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: Baseline and Year 2
Objective 2 Primary Outcome: Relationship Between Total Fat Accumulation and Change in Sedentary Behavior - Body Fat (%)
Body composition will be determined by DXA and MRI. With DXA, total body fat and trunk fat will be measured by whole-body DXA using a GE iDXA scanner (GE Medical Systems, Milwaukee, WI) to quantify total and regional body fat (including trunk fat). MRI - Visceral fat, i.e. visceral adipose tissue, will be measured by water-fat shifting MRI using the General Electric Discovery 750w 3.0 Tesla (GE Medical Systems, Milwaukee, WI). IDEAL-IQ imaging technique will be used to generate water-only, fat-only, in-phase, and out-of-phase echoes in a single acquisition with a 20-second breath-hold. Sedentary behavior will be measured by a a triaxial accelerometer as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2
Objective 2 Primary Outcome: Relationship Between Total Fat Accumulation and Change in Sedentary Behavior. - Waist Circumfrence
Body composition will be determined by DXA and MRI. With DXA, total body fat and trunk fat will be measured by whole-body DXA using a GE iDXA scanner (GE Medical Systems, Milwaukee, WI) to quantify total and regional body fat (including trunk fat). MRI - Visceral fat, i.e. visceral adipose tissue, will be measured by water-fat shifting MRI using the General Electric Discovery 750w 3.0 Tesla (GE Medical Systems, Milwaukee, WI). IDEAL-IQ imaging technique will be used to generate water-only, fat-only, in-phase, and out-of-phase echoes in a single acquisition with a 20-second breath-hold. Sedentary behavior will be measured by a a triaxial accelerometer as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2
Objective 1 Secondary Analysis: Change in Daily Moderate to Vigorous Physical Activity (MVPA) Minutes Between Years.
MVPA measured by a triaxial accelerometer (Actigraph GT3X+, Actigraph of Ft. Walton Beach, FL) as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2
Objective 1 Secondary Analysis: Change in Days/Week of Physical Activity Between Years.
MVPA measured by a triaxial accelerometer (Actigraph GT3X+, Actigraph of Ft. Walton Beach, FL) as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2
Objective 2 Secondary Analysis: Relationship Between Fat Mass Accumulation and Change in Physical Activity.
Body composition will be determined by DXA and MRI. With DXA, total body fat and trunk fat will be measured by whole-body DXA using a GE iDXA scanner (GE Medical Systems, Milwaukee, WI) to quantify total and regional body fat (including trunk fat). MRI - Visceral fat, i.e. visceral adipose tissue, will be measured by water-fat shifting MRI using the General Electric Discovery 750w 3.0 Tesla (GE Medical Systems, Milwaukee, WI). IDEAL-IQ imaging technique will be used to generate water-only, fat-only, in-phase, and out-of-phase echoes in a single acquisition with a 20-second breath-hold. Physical Activity will be measured by a triaxial accelerometer as described in outcome 1. Participants will also complete a Lifestyle survey to collect information including physical activity habits.
Time frame: Baseline and Year 2