The Impact of Leg Immobilization on Postabsorptive and Postprandial Muscle Protein Breakdown in Healthy Young Males

The present study will seek the quantify the simultaneous muscle protein synthesis and breakdown response with and without amino acid provision in humans following 2 days of immobilisation.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Other: Postabsorptive; Procedure: Immobilisation; Other: Postprandial

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Devon
    • Exeter, Devon, United Kingdom, EX1 2LU
      • University of Exeter

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Male
• 18-40 years of age
• Body mass index between 18.5 and 30

Exclusion Criteria:

• 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 epilepsy, seizures or schizophrenia
• Any known disorders in muscle metabolism
• Regular use of nutritional supplements
• Allergy to lidocaine
• Allergy to one or multiple amino acids
• Recent (within the last 6 months) or current musculoskeletal injury (e.g. leg fracture) as these could be exacerbated by the intervention e.g. unilateral leg immobilisation, or mean the participant is unable to use crutches.
• Having received or ingested a stable isotope tracer in the past

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Postabsorptive; Saline infusion to mimic postabsorptive circulating amino acid concentrations	Other: Postabsorptive; Saline will be infused to mimic postabsorptive circulating amino acid concentrations; Procedure: Immobilisation; One leg will undergo 2 days immobilisation prior to the test day
Active Comparator: Postprandial; Amino acid infusion to mimic postprandial circulating amino acid concentrations	Procedure: Immobilisation; One leg will undergo 2 days immobilisation prior to the test day; Other: Postprandial; An amino acid infusate will be administered to mimic postprandial circulating amino acid concentrations

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle protein breakdown rate	Muscle protein breakdown rate (FBR, measured in %/h) during 1 hour of saline or amino acid infusion	1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle protein breakdown rate	Muscle protein breakdown rate (FBR, measured in %/h) during 3 hours of saline or amino acid infusion	3 hours
Muscle protein synthesis rate	Muscle protein synthesis rate (FSR, measured in %/h) during 3 hours of saline or amino acid infusion measured using a D5 phenylalanine infusion	3 hours

Collaborators and Investigators

• Sponsor: University of Exeter
• Investigators: Principal Investigator: Marlou Dirks, PhD, University of Exeter

Study record dates

Study Major Dates

• Study Start (Actual): April 15, 2019
• Primary Completion (Actual): March 17, 2020
• Study Completion (Actual): January 9, 2023

Study Registration Dates

• First Submitted: April 16, 2019
• First Submitted That Met QC Criteria: April 29, 2019
• First Posted (Actual): May 2, 2019

Study Record Updates

• Last Update Posted (Actual): March 22, 2023
• Last Update Submitted That Met QC Criteria: March 21, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: 180509/B/01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No