Summertime: Kids in Motion

Study Overview
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Brief Summary
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This is a 3-week randomized crossover study to determine the effect of the prior night's sleep duration on energy-balance related behaviors of diet and physical activity the following day. In Week 1, child participants will sleep their usual amount. In week 2, participants will be randomized to either a sleep restricted or a healthy sleep condition for 4 nights. In week 3, participants will cross over to the opposite sleep condition for 4 nights.

Detailed Description
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Individuals of Mexican descent comprise the largest proportion of the Latino population in the United States and they suffer high rates of obesity. Short sleep is a risk factor for obesity. An improved understanding of the underlying behavioral mechanisms by which short sleep duration may impact obesity among Mexican American children is critical to prevent and/or reduce obesity and chronic disease in this population. This research will focus on behavioral mechanisms (i.e., diet and physical activity) that link sleep duration to obesity. Mexican American 8-10-year-olds will participate in a 3-week crossover study to examine: 1) contextual factors (i.e., bedtime routines, sleep hygiene, familism) that may impact sleep; and 2) the impact of prior night's sleep duration on diet and physical activity the subsequent day. This research design will make it possible to examine whether sufficient sleep is protective of energy balance (e.g., healthful dietary intake/patterns and physical activity) as well as contextual factors related sleep.

Official Title
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Sleep Duration and Risk for Obesity in Mexican American Children

Conditions
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Sleep

Intervention / Treatment
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* Behavioral: Short sleep
* Behavioral: Long sleep


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Mexican American child-mother pairs which will include: child 8-10 years old; mother/female guardian; English/Spanish speakers; mobile phone user. Exclusion Criteria: Children with major illnesses and/or with sleep apnea for which children In families where 2 children are eligible for participation, a child will be selected at random to participate in the study. The investigators will exclude fathers from this study for reasons due to statistical power

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 10 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Three-week study includes: Week 1 - all children get usual sleep Tuesday-Friday. Week 2 - children are randomized to getting no more than 8 hours or at least 10 hours of sleep (Tuesday-Friday). Week 3 - children crossover to the opposite sleep condition (Tuesday-Friday).
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Short sleep<br>No more than 8 hours of sleep for 4 consecutive nights. | Behavioral: Short sleep<br>* Child will be asked to sleep for less than 8 hours. Study team will help parent design a sleep schedule for that week. Study team will send parent daily text messages or phone call reminders.<br>* Other names: Restricted sleep;Behavioral: Long sleep<br>* Child will be asked to sleep for more than 10 hours. Study team will help parent design a sleep schedule for that week. Study team will send parent text messages or phone call reminders.<br>* Other names: Healthy sleep;|
| Experimental: Long sleep<br>At least 10 hours of sleep for 4 consecutive nights | Behavioral: Short sleep<br>* Child will be asked to sleep for less than 8 hours. Study team will help parent design a sleep schedule for that week. Study team will send parent daily text messages or phone call reminders.<br>* Other names: Restricted sleep;Behavioral: Long sleep<br>* Child will be asked to sleep for more than 10 hours. Study team will help parent design a sleep schedule for that week. Study team will send parent text messages or phone call reminders.<br>* Other names: Healthy sleep;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The effect of short sleep the prior night on eating (outcome) the subsequent day. | Sleep duration will be measured with accelerometers. Eating/dietary intake (outcome) will be assessed on Thursdays and Fridays using 24-hour recalls using Nutrition Data System for Research. Caloric intake (kcals) will be calculated. | One week | 
| The effect of short sleep the prior night on physical activity (outcome) the subsequent day. | Sleep duration will be measured with accelerometers. Physical activity will be measured with accelerometers (same as for sleep). Accelerometer data will be used to calculate moderate- to vigorous-intensity physical activity (minutes). | One week | 
| The effect of long sleep the prior night on eating (outcome) the subsequent day. | Sleep duration will be measured with accelerometers. Eating/dietary intake (outcome) will be assessed on Thursdays and Fridays using 24-hour recalls using Nutrition Data System for Research. Sleep duration will be measured with accelerometers. Dietary intake (outcome) will be assessed on Thursdays and Fridays using 24-hour recalls using Nutrition Data System for Research. Healthy Eating Index scores (range 1-10) will be calculated. | One week | 
| The effect of long sleep the prior night on eating (outcome) the subsequent day. | Sleep duration will be measured with accelerometers. Eating/dietary intake (outcome) will be assessed on Thursdays and Fridays using 24-hour recalls using Nutrition Data System for Research. Sleep duration will be measured with accelerometers. Dietary intake (outcome) will be assessed on Thursdays and Fridays using 24-hour recalls using Nutrition Data System for Research. Daily sugar intake (grams) will be calculated. | One week | 
| The effect of long sleep the prior night on physical activity the subsequent day. | Sleep duration will be measured with accelerometers. Physical activity will be measured with accelerometers (same as for sleep). Accelerometer data will be used to calculate moderate- to vigorous-intensity physical activity (minutes). | One week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Family sleep schedules related to children's sleep duration. | Parent and child bedtimes and wakeup times will be assessed by parent report. Sleep duration will be measured with accelerometers (minutes). | Baseline measurement (one time point) | 
| Family acculturation factors related to children's sleep schedules. | Acculturation will be assessed using the bidimensional acculturation scale for Hispanics (range 1-5; Marin & Gamba, 1996). Child sleep schedule (bedtime) will be measured by parent report. | Baseline measurement (one time point) | 
| Sleep hygiene related to children's sleep schedules. | Sleep hygiene will be assessed by whether the child shares a bed, shares a room and a bed, shares a room (but not a bed), or does not any. Child sleep schedule (bedtime) will be measured by parent report. | Baseline measurement (one time point) | 
| Sleep hygiene related to children's sleep schedules. | Sleep hygiene will be assessed by whether the child shares a bed, shares a room and a bed, shares a room (but not a bed), or does not any. Child sleep schedule (wake time) will be measured by parent report. | Baseline measurement (one time point) |