Healthy, Obesity, Overweight
Conditions
Keywords
Metabolism, Children, Walking Bouts, Glucose, Insulin
Brief summary
Background: Some studies have found that people can better process sugars when they take walking breaks. Studies have also found that children's attention and memory may improve after exercise. It is not known if short walking breaks have the same effects. Researchers want to study if breaking up sitting with walking for 6 days helps children s bodies use sugars and improves concentration. Objectives: To learn if breaking up sedentary (low-activity) time with short walking breaks over 6 days affects how children s bodies use sugar. To learn if breaking up sedentary time changes children s attention, memory, feelings, activity, or eating. Eligibility: Children ages 7-11 in general good health Design: Participants will be screened with: * Medical history * Physical exam * Fasting blood tests. On 2 out of 7 total study visits, participants cannot eat or drink after 10 p.m. the night before. * Full-body X-ray * EKG (Electronic signals that record heart function through stickers) * Treadmill exercise. Heart, blood pressure, and oxygen will be monitored. * Questions about the child s health, socialization, and activity, and parent s education and economic status * Picture vocabulary test * Dietician meeting (Questions about eating habits) Participants will have visits on 6 consecutive days. Over that time, they will wear 2 devices to monitor blood sugar and activity (even while at home). Participants will have 5 after-school visits. These include: * Health check * Snack plus food for the next 24 hours * Activity monitored * 3-hour sitting tests. Participants will do non-active things. Some will have 3-minute walks every 30 minutes. * Cognitive tests and questions about mood and anxiety are given on days #1 & 5. Participants will fast before the last visit in the morning. They will have: * 9 blood draws by IV catheter. Participants will drink sugar water. * Sitting test * Activity monitored * Meal (food buffet)
Detailed description
Background: Sedentary behavior is defined as a set of low-intensity activities involving limited body movement (e.g.: TV viewing, prolonged sitting). Some studies have found higher levels of childhood sedentary behavior predict higher body mass index (BMI) and metabolic abnormalities. We and others have found that interrupting sitting with short, 2-3 minute bouts of moderate activity (walking) can improve glucose tolerance during a single session. Thus, interrupting sedentary behavior may be an intervention strategy to reduce health risks. Objective: We propose to conduct a randomized pilot study to assess whether interrupting sedentary behavior for 6 consecutive days provides sustained improvement in carbohydrate metabolism without negatively impacting executive function, attention, mood, anxiety, dietary intake or usual physical activity. Design & Population: Using a randomized parallel group design, children, ages 7-11 years, will complete an assigned randomized condition of either 6 consecutive days of 3 hours of monitored sedentary activity (sitting) or 6 consecutive days of 3 hours of interrupted sitting (in which they will be prompted to walk for 3 minutes every 30 minutes). Outcome measures: Twenty-four-hour continuous glucose monitoring and postprandial insulin incremental area under the curve (iAUC) on post-condition oral glucose tolerance testing will be the primary measures. Secondary measures include: postprandial glucose iAUC, executive function, attention, mood, anxiety, dietary intake, and free-living physical activity. Impact: This project will investigate if consecutive daily interruption of sitting behaviors improves glucose tolerance, a potential negative health consequences of sedentary behavior in children. If repeatedly interrupting sitting with short bouts has sustained beneficial effects among children, interventions examining the frequency, duration, and intensity of such interruptions could be developed for use in the community setting. Thus, these results have the potential to provide insight into novel behavioral intervention targets in youth.
Interventions
OTHERWalking Bouts
Six daily 3 hour sessions with prompted 3-minute moderate-intensity walking bouts performed on a treadmill every 30 minutes throughout the 3 hour duration. There will be a total of 6 walking bouts (18 minutes total) each day. Moderate-intensity walking speed and grade will be selected to achieve 80% of the heart rate achieved at the ventilatory threshold as determined during a V02max test.
OTHERSedentary
(Control 'intervention') Six daily 3 hour sessions with no physical activity (i.e. subject remains sedentary in seated or recumbent position) throughout the 3 hour duration.
Sponsors
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
7 Years to 11 Years
Healthy volunteers
No
Inclusion criteria
* INCLUSION CRITERIA: Participants will qualify for the study if they meet the following criteria: 1. Good general health. 2. Age greater than or equal to 7 and less than 12 years. 3. Fasting plasma glucose less than 100 mg/dL 4. Body mass index (BMI) greater than or equal to the 5th percentile, as determined by the CDC age- and sex- specific growth charts.
Exclusion criteria
Participants will be excluded from the study for: 1. Significant cardiac or pulmonary disease likely to or resulting in hypoxia or decreased perfusion. 2. Evidence of impaired glucose tolerance or type 2 diabetes, including fasting plasma glucose greater than or equal to 100 mg/dL. 3. Presence of other endocrinologic disorders leading to obesity (e.g.: Cushing Syndrome). 4. Participants who have, or whose parent/guardians have, current substance abuse or a psychiatric disorder or other condition that, in the opinion of the investigators, would impede competence, compliance, or prevent the completion of the study. 5. Participants who have, or are currently receiving, anti-psychotic drugs that would affect metabolism, cognitive outcomes, and body habitus. 6. Participants receiving medical treatment other than diet for hypertension or dyslipidemia. 7. Participants with precocious puberty and/or receiving androgen and estrogen therapy. 8. Participants currently taking medications for ADHD, or any disorder or use of medications known to affect body composition or weight including but not limited to glucocorticoids or other steroid compounds. 9. Presence of pre-existing neurocognitive disabilities, or an age-adjusted score below 85 on the Picture Vocabulary Test at the screening visit. 10. Presence of food allergies, such as peanut/tree nut, dairy, soy or any other food allergy or personal dietary restrictions that would preclude participant from consuming the daily diet or the buffet. 11. Presence of significant skin disease or allergy to adhesive material prohibiting placement of a continuous glucose monitor. 12. Participants unable or unwilling to abstain from acetaminophen, ascorbic acid, or salicylic acid during study duration. 13. Participant does not speak fluent English. 14. Participant is or becomes pregnant. 15. Participant has an ambulatory impairment OPTIONAL MRS SUPPLEMENTAL ARM INCLUSION CRITERIA (a) Participants will qualify for the study if they qualify for the primary Break It Up! study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Insulin iAUC Obtained During the Oral Glucose Tolerance Test at the Final Experimental Visit. | test day 6 | Insulin integrated area under the curve (iAUC) as a marker of glucose metabolism on OGTT during test day #6, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| C-Peptide iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | test day 6 | Integrated area under the curve (iAUC) for C-Peptide values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion |
| Free Fatty Acid iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | test day 6 | Integrated area under the curve (iAUC) for Free Fatty Acid values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion |
| Daily Physical Activity (Step Counts/Min) During Intervention. | test days 1-6 | Mean 3-dimensional activity during the 3 hours of intervention from all days (step counts per minute) |
| Daily Physical Activity (3-dimensional Activity Counts/Day) Outside of the Intervention. | test days 1-6 | Mean total daily 3-dimensional activity counts during the 21 hours without intervention on days 1-6 (activity counts/21 hours) from triaxial write accelerometers worn at home. Note: these are not step counts but total 3D activity counts because motion of the wrist at times other than walking are also recorded. There is no simple way to convert these counts to step counts. |
| Glucose iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | test day 6 | Integrated area under the curve (iAUC) for glucose values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion |
| Percentage Fat Intake at the Final Test Meal. | test day 6 | Percentage Energy intake from Fat during buffet meal immediately after the end of intervention |
| Percentage Carbohydrate Intake at the Final Test Meal. | test day 6 | Percentage Energy intake from Carbohydrate during buffet meal immediately after the end of intervention |
| Percentage Protein Intake at the Final Test Meal. | test day 6 | Percentage Energy intake from Protein during buffet meal immediately after the end of intervention |
| Energy Intake at the Final Test Meal. | test day 6 | Total energy intake (kcal) during buffet meal immediately after the end of intervention |
Countries
United States
Participant flow
Recruitment details
Participants were recruited via multiple methods: 1. Letters were mailed to local parents 2. Flyers were posted with permission. 3. Local community groups were asked to send the flyer to their listservs. 4. Schools, churches, pediatricians, and community centers were contacted. 5. Potential volunteers in ResearchMatch program were contacted.
Pre-assignment details
Of the 129 participants who were evaluated with baseline screening, 20 were not studied further: * 12: Failed to meet inclusion criteria * 2: Impaired glucose tolerance * 1: Hepatic disease * 7: Failed picture vocabulary test * 2 Did not meet BMI criteria * 6: No longer interested * 1: Could not determine VO2 max or lactate threshold from exercise testing (insufficient effort) * 1: Withdrawn due to COVID pandemic restrictions
Participants by arm
| Arm | Count |
|---|---|
| Sedentary (Control intervention) Six daily 3 hour sessions with no physical activity (i.e. subject remains sedentary in seated or recumbent position) throughout the 3 hour duration.
Sedentary: (Control 'intervention') Six daily 3 hour sessions with no physical activity (i.e. subject remains sedentary in seated or recumbent position) throughout the 3 hour duration. | 42 |
| Walking Bouts Six daily 3 hour sessions with prompted 3-minute moderate-intensity walking bouts performed on a treadmill every 30 minutes throughout the 3 hour duration. There will be a total of 6 walking bouts (18 minutes total) each day. Moderate-intensity walking speed and grade will be selected to achieve 80% of the heart rate achieved at the ventilatory thresholdas determined during a V02max test.
Walking Bouts: Six daily 3 hour sessions with prompted 3-minute moderate-intensity walking bouts performed on a treadmill every 30 minutes throughout the 3 hour duration. There will be a total of 6 walking bouts (18 minutes total) each day. Moderate-intensity walking speed and grade will be selected to achieve 80% of the heart rate achieved at the ventilatory threshold as determined during a V02max test. | 51 |
| Total | 93 |
Baseline characteristics
| Characteristic | Sedentary | Walking Bouts | Total |
|---|---|---|---|
| Age, Continuous | 10.4 years STANDARD_DEVIATION 1.3 | 10.0 years STANDARD_DEVIATION 1.2 | 10.2 years STANDARD_DEVIATION 1.3 |
| BMI (kg/m2) | 21.2 kg/m2 STANDARD_DEVIATION 6.6 | 19.9 kg/m2 STANDARD_DEVIATION 3.9 | 20.5 kg/m2 STANDARD_DEVIATION 5.3 |
| BMI z-score | 0.8 z-score STANDARD_DEVIATION 1.2 | 0.8 z-score STANDARD_DEVIATION 0.9 | 0.8 z-score STANDARD_DEVIATION 1 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 6 Participants | 8 Participants | 14 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 36 Participants | 43 Participants | 79 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Fasting glucose (mg/dL) | 87.6 mg/dL STANDARD_DEVIATION 6.8 | 87.9 mg/dL STANDARD_DEVIATION 5.9 | 87.8 mg/dL STANDARD_DEVIATION 6.3 |
| Fasting insulin (mIU/ml) | 11.1 mIU/mL STANDARD_DEVIATION 9.8 | 9.7 mIU/mL STANDARD_DEVIATION 5.9 | 10.4 mIU/mL STANDARD_DEVIATION 7.4 |
| Fat Mass (kg) | 16.2 kg STANDARD_DEVIATION 12.4 | 13.5 kg STANDARD_DEVIATION 6.9 | 14.7 kg STANDARD_DEVIATION 9.8 |
| Height (cm) | 146.0 cm STANDARD_DEVIATION 9.8 | 141.2 cm STANDARD_DEVIATION 8.5 | 143.4 cm STANDARD_DEVIATION 9.4 |
| IPAQ score | 2.2 units on a scale (1-4) STANDARD_DEVIATION 1 | 2.2 units on a scale (1-4) STANDARD_DEVIATION 1.1 | 2.2 units on a scale (1-4) STANDARD_DEVIATION 1 |
| Lean Mass (kg) | 28.9 kg STANDARD_DEVIATION 7.9 | 25.5 kg STANDARD_DEVIATION 4.8 | 27.0 kg STANDARD_DEVIATION 6.6 |
| Peak VO2 (ml/kg/min) | 38.3 ml/kg/min STANDARD_DEVIATION 9.1 | 38.5 ml/kg/min STANDARD_DEVIATION 7.4 | 38.4 ml/kg/min STANDARD_DEVIATION 8.1 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 3 Participants | 2 Participants | 5 Participants |
| Race (NIH/OMB) Black or African American | 9 Participants | 5 Participants | 14 Participants |
| Race (NIH/OMB) More than one race | 2 Participants | 3 Participants | 5 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 3 Participants | 4 Participants |
| Race (NIH/OMB) White | 27 Participants | 38 Participants | 65 Participants |
| Region of Enrollment United States | 42 Participants | 51 Participants | 93 Participants |
| Sex: Female, Male Female | 18 Participants | 27 Participants | 45 Participants |
| Sex: Female, Male Male | 24 Participants | 24 Participants | 48 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 42 | 0 / 51 |
| other Total, other adverse events | 0 / 42 | 0 / 51 |
| serious Total, serious adverse events | 0 / 42 | 0 / 51 |
Outcome results
Primary
Insulin iAUC Obtained During the Oral Glucose Tolerance Test at the Final Experimental Visit.
Insulin integrated area under the curve (iAUC) as a marker of glucose metabolism on OGTT during test day #6, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion
Time frame: test day 6
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Insulin iAUC Obtained During the Oral Glucose Tolerance Test at the Final Experimental Visit. | 13,698.60 mIU/dL∙min | Standard Deviation 9414.9 |
| Walking Bouts | Insulin iAUC Obtained During the Oral Glucose Tolerance Test at the Final Experimental Visit. | 10,619.70 mIU/dL∙min | — |
p-value: 0.00595% CI: [-0.17, -0.03]ANCOVA
Secondary
C-Peptide iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention.
Integrated area under the curve (iAUC) for C-Peptide values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion
Time frame: test day 6
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | C-Peptide iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 1,292.10 ng/dL∙min | Standard Deviation 449.8 |
| Walking Bouts | C-Peptide iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 1,160.10 ng/dL∙min | Standard Deviation 448.8 |
p-value: 0.04595% CI: [-0.084, -0.002]ANCOVA
Secondary
Daily Physical Activity (3-dimensional Activity Counts/Day) Outside of the Intervention.
Mean total daily 3-dimensional activity counts during the 21 hours without intervention on days 1-6 (activity counts/21 hours) from triaxial write accelerometers worn at home. Note: these are not step counts but total 3D activity counts because motion of the wrist at times other than walking are also recorded. There is no simple way to convert these counts to step counts.
Time frame: test days 1-6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from one participant randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Daily Physical Activity (3-dimensional Activity Counts/Day) Outside of the Intervention. | 2.1 activity counts per 21 hours x 10^6 | Standard Deviation 0.6 |
| Walking Bouts | Daily Physical Activity (3-dimensional Activity Counts/Day) Outside of the Intervention. | 2.2 activity counts per 21 hours x 10^6 | Standard Deviation 0.5 |
p-value: 0.3995% CI: [-0.33, 0.13]t-test, 2 sided
Secondary
Daily Physical Activity (Step Counts/Min) During Intervention.
Mean 3-dimensional activity during the 3 hours of intervention from all days (step counts per minute)
Time frame: test days 1-6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from one participant randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Daily Physical Activity (Step Counts/Min) During Intervention. | 5.4 step count per minute | Standard Deviation 1.9 |
| Walking Bouts | Daily Physical Activity (Step Counts/Min) During Intervention. | 11.2 step count per minute | Standard Deviation 3 |
p-value: <0.00195% CI: [-6.884, -4.716]t-test, 2 sided
Secondary
Energy Intake at the Final Test Meal.
Total energy intake (kcal) during buffet meal immediately after the end of intervention
Time frame: test day 6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from two participants randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Energy Intake at the Final Test Meal. | 1,312.4 kcal | Standard Deviation 478.4 |
| Walking Bouts | Energy Intake at the Final Test Meal. | 1,207.4 kcal | Standard Deviation 443.8 |
p-value: 0.64895% CI: [-0.071, 0.114]ANCOVA
Secondary
Free Fatty Acid iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention.
Integrated area under the curve (iAUC) for Free Fatty Acid values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion
Time frame: test day 6
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Free Fatty Acid iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 39.7 mmol/L∙min | Standard Deviation 9.8 |
| Walking Bouts | Free Fatty Acid iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 38.5 mmol/L∙min | Standard Deviation 13.1 |
p-value: 0.22695% CI: [-0.051, 0.013]ANCOVA
Secondary
Glucose iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention.
Integrated area under the curve (iAUC) for glucose values during the oral glucose tolerance test, collected at 0, 30, 60, 90, 120, 150, and 180 minutes after oral dextrose ingestion
Time frame: test day 6
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Sedentary | Glucose iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 22,247.90 mg/dL∙min |
| Walking Bouts | Glucose iAUC Obtained During the Oral Glucose Tolerance Test on Day # 6 of Intervention. | 21,688.80 mg/dL∙min |
p-value: 0.34995% CI: [-0.033, 0.011]ANCOVA
Secondary
Percentage Carbohydrate Intake at the Final Test Meal.
Percentage Energy intake from Carbohydrate during buffet meal immediately after the end of intervention
Time frame: test day 6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from two participants randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Percentage Carbohydrate Intake at the Final Test Meal. | 52.0 percentage of total energy intake (%) | Standard Deviation 9 |
| Walking Bouts | Percentage Carbohydrate Intake at the Final Test Meal. | 51.8 percentage of total energy intake (%) | Standard Deviation 8.4 |
p-value: 0.5595% CI: [-4.57, 2.45]ANCOVA
Secondary
Percentage Fat Intake at the Final Test Meal.
Percentage Energy intake from Fat during buffet meal immediately after the end of intervention
Time frame: test day 6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from two participants randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Percentage Fat Intake at the Final Test Meal. | 35.8 percentage of total energy intake (%) | Standard Deviation 7 |
| Walking Bouts | Percentage Fat Intake at the Final Test Meal. | 36.2 percentage of total energy intake (%) | Standard Deviation 6 |
p-value: 0.53995% CI: [-1.857, 3.525]ANCOVA
Secondary
Percentage Protein Intake at the Final Test Meal.
Percentage Energy intake from Protein during buffet meal immediately after the end of intervention
Time frame: test day 6
Population: Data were unavailable from two participants randomized to the Sedentary condition and from two participants randomized to the Walking Bouts condition.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sedentary | Percentage Protein Intake at the Final Test Meal. | 12.2 percentage of total energy intake (%) | Standard Error 3.6 |
| Walking Bouts | Percentage Protein Intake at the Final Test Meal. | 12.0 percentage of total energy intake (%) | Standard Error 3.2 |
p-value: 0.74195% CI: [-1.127, 1.579]ANCOVA