Effect of a Protein-enriched Drink on Muscle Function

Study Overview
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Brief Summary
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There is no conclusive evidence about the effect of intake of protein-enriched drink after and acute high intensity exercise bout on muscle function and damage. The investigators aimed to study the effect of a protein-enriched drink on muscle function recovery following an acute high intensity exercise bout. The present counterbalanced, crossover, and double blind study will involve a total of 12 active men.

Detailed Description
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Participants will run downhill (-10%) during 30 min at a intensity equivalent to 75-80% of their maximum heart rate (previously determined). After the exercise bout, participants will have either the placebo or the experimental drink. The investigators will measure muscle function and damage-related parameters right after the exercise as well as the three following days. This protocol will be repeated after a wash out period of 3 weeks, where the participants will have the other drink. The investigators will control exercise and diet three weeks before study entry, during the experimental week as the investigators as during the wash out period.

Official Title
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Effect of a Protein-enriched Drink on Muscle Function Recovery Following an Acute High Intensity Exercise Bout

Conditions
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Contracture

Intervention / Treatment
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* Dietary Supplement: Protein-enriched drink


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Recreational triathletes with 2 years of experience Maximum oxygen uptake : ≥55 ml/kg/min Fat mass: 8-20% measured by dual energy x-ray absorptiometry Not participating in another study Not having ergogenic aids Not participating in a weight loss program Normal electrocardiogram Participants must be capable and willing to provide consent, understand exclusion criteria and accept the randomized group assignment Exclusion Criteria: History of cardiovascular disease Diabetes or hypertension Medication for hypertension, hyperlipidemia, hyperuricemia or other illness. Smoking Other significant medical conditions that are life-threatening or that can interfere with or be aggravated by exercise. Unwillingness to either complete the study requirements or to be randomized into control or training group.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Male

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
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control<br>330 ml of commercial protein-enriched drink (2.5 g/100 ml of protein) | |
| Experimental: Experimental<br>330 ml of protein-enriched drink (6 g/100 ml of protein) | Dietary Supplement: Protein-enriched drink<br>* Participants will drink 330 ml of a protein-enriched drink (6 g/ml of protein) after a high intensity exercise that induce muscle damage (30 min running downhill with a slope of -10º)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Isometric muscle strength | Isometric muscle strength of lower limbs at 90% angle. | Change from pre- protein-enriched drink to 24, 48 and 72 hrs post- protein-enriched drink | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle soreness of lower limbs self-reported by a visual anagogic scale and with an algometer score. | Muscle soreness of the lower limbs will be self-reported by a visual anagogic scale and with an algometer score. | Change from post- protein-enriched drink to 24, 48 and 72 hrs post- protein-enriched drink | 
| Power output assessed with the 30sec. Wingate anaerobic test | Power output will be assessed with the 30sec. Wingate anaerobic test. | Change from post- protein-enriched drink to 24, 48 and 72 hrs post- protein-enriched drink | 
| Creatine kinase | Creatine kinase will be assessed after the protein-enriched drink to assess muscle recovery after a high intensity exercise bout | Change from post- protein-enriched drink to 24, 48 hrs post- protein-enriched drink | 
| Urine Creatinine | Concentration of creatinine in urine will be assessed after the protein-enriched drink to assess muscle recovery after a high intensity exercise bout | Change from post- protein-enriched drink to 24, 48 hrs post- protein-enriched drink | 
| Resting metabolic rate |  | Change from pre- protein-enriched drink to 24, 48 and 72 hrs post- protein-enriched drink | 
| Time limit (time that the participant is able to run 90% of his determined maximum aerobic velocity) | We will measure the time that the participant is able to run 90% of his determined maximum aerobic velocity | 24hrs after protein-enriched drink | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Muscle function, Anaerobic power, Muscle damage