Two-day Bed Rest, Insulin Sensitivity and Muscle Protein Synthesis

Study Overview
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Brief Summary
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The impact of two days bed rest versus two days of habitual activity on insulin sensitivity and cumulative muscle protein synthesis will be investigated in healthy young males

Detailed Description
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To study the mechanisms underlying inactivity-induced muscle atrophy, the impact of two days bed rest versus two days of habitual activity on insulin sensitivity and cumulative muscle protein synthesis will be investigated in healthy young males

Official Title
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The Impact of Two Days of Bed Rest Versus Two Days of Habitual Activity on Insulin Sensitivity and Cumulative Muscle Protein Synthesis in Healthy Young Males

Conditions
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Healthy

Intervention / Treatment
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* Behavioral: Habitual activity
* Behavioral: Bed rest


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male Aged 18-40 Exclusion Criteria: Smoker Any diagnosed metabolic impairment (e.g. type 1 or 2 Diabetes) Any diagnosed cardiovascular disease (e.g. deep vein thrombosis or hypertension) Chronic use of any prescribed or over the counter pharmaceuticals (that may modulate muscle protein metabolism). A personal or family history of thrombosis, epilepsy, seizures or schizophrenia. Any known disorders in muscle metabolism Regular use of nutritional supplements (i.e. ingestion more than twice per week during the last month) Metallic implants (including heart pacemaker, cochlear implants, medication pumps, surgical clips, plates or screws). Allergy to lidocaine Recent (within the last 6 months) or current musculoskeletal injury (e.g. leg fracture)

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: Basic Science
Intervention Model: Single Group Assignment
Interventional Model Description: Participants will firstly undergo 2 days of habitual physical activity, followed by 2 days of bed rest
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Habitual activity and 2 days bed rest<br>Participants will undergo 2 days of habitual activity and 2 days bed rest | Behavioral: Habitual activity<br>* Two days of habitual physical activity, under normal free-living conditions<br>Behavioral: Bed rest<br>* Two days of bed rest, to induce whole-body physical inactivity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in whole-body insulin sensitivity | Change in whole-body insulin sensitivity via meal tolerance test | During 2 days of habitual physical activity and 2 days of bed rest. Blood glucose and insulin are monitored for 2 hours following ingestion of a standardized meal | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in cumulative muscle protein synthesis | Cumulative muscle protein synthesis via deuterium oxide ingestion. The incorporation of deuterated alanine in muscle is expressed relative to body water enrichments, to obtain muscle protein synthesis in %/day | During 2 days of habitual physical activity and 2 days of bed rest | 
| Change in continuous glucose | Change in continuous glucose via continuous glucose monitoring. | Continuous glucose, during the 2 days of habitual activity and 2 days of bed rest | 
| Change in muscle volume | Change in muscle volume via MRI | Immediately before and immediately after the 2-day bed rest period |