Post-exercise Protein Intake for Active Children

Study Overview
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Brief Summary
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Today, there is an important lack of knowledge on the effects of dietary protein on protein metabolism after physical activity in children. Here, the investigators will measure changes in whole body protein metabolism using minimally invasive techniques and stable isotope methodology at rest and after physical activity with the intake of milk protein.

Official Title
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Double Blind Controlled Trial of Protein in Active Children

Conditions
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Child

Intervention / Treatment
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* Other: nutrition


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy and physically active (as determined by medical and activity questionnaire) 10-12 years of age Within approximately 2 years of estimated age of peak height velocity (PHV) Minimum aerobic fitness of 35 ml/kg/min as assessed by the McMaster All-out Progressive Continuous Cycling Protocol Having obtained his/her informed assent Having obtained his/her legal representative's informed consent Exclusion Criteria: Post-pubertal Taking any medication Smoker Undergoing medical treatment or investigations Body mass index > 24 Suffer from chronic diseases (with regular intake of drugs, medical history) Vegetarians Vaccination in the last 4 months Any know food allergies or intolerance Pregnancy Special diet or weight loss program (e.g. Atkins diet) Acute illness Fever, cold, flu Participation in a cholesterol management program with functional foods like food supplement enriched in omega-3 fatty acids, dairy products enriched with phytosterols (margarines, yoghurts).

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 12 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control<br>placebo | Other: nutrition<br>* protein-based food<br>|
| Active Comparator: High protein intake<br>Nutrition - High protein | Other: nutrition<br>* protein-based food<br>|
| Active Comparator: Low protein intake<br>Nutrition - Low protein | Other: nutrition<br>* protein-based food<br>|
| Active Comparator: Medium protein intake<br>Nutrition - Medium protein | Other: nutrition<br>* protein-based food<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Whole body protein balance | Whole body protein balance will be measured by stable isotopes. | Participants will be followed for 10 days prior to assessment of whole body protein balance. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Whole body protein metabolism, metabolites | Whole body protein metabolism by stable isotopes and metabolite concentrations in plasma and urine. | Participants will be followed for 10 days prior to assessment of whole body protein metabolism and metabolites |