Immobilization Effects on Muscle Atrophy

Recruiting in Palo Alto (17 mi)

Overseen by Emily E Howard, PhD

Age: 18 - 65

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Waitlist Available

Sponsor: United States Army Research Institute of Environmental Medicine

No Placebo Group

Trial Summary

What is the purpose of this trial?

This study will characterize intramuscular molecular mechanisms underlying anabolic resistance to protein ingestion during muscle disuse. Adults (n=12) will be studied using a unilateral leg immobilization model in which one leg will be randomly assigned to immobilization and the contralateral, active leg used as a within-subjects control. Immobilization will be implemented for five days using a rigid knee brace, during which time participants will ambulate using crutches. Integrated ribonucleic acid (RNA) synthesis will be determined during immobilization in the immobilized and non-immobilized legs using ingested deuterium oxide, salivary and blood sampling, and muscle biopsies. Immediately after immobilization, muscle biopsies will be collected before and 90 mins after consuming 25 g of whey protein from the immobilized and non-immobilized legs to characterize the intramuscular molecular response to protein feeding. Serial blood samples will be collected during that time to characterize the circulating metabolic response to protein ingestion. Knowledge generated from this effort will inform the development of targeted interventions for mitigating anabolic resistance to protein ingestion that develops during periods of muscle disuse.

Research Team

Emily E Howard, PhD

Principal Investigator

US Army Research Institute of Environmental Medicine

Eligibility Criteria

This trial is for healthy adults aged 18-39, with a BMI of 18.5-30, who exercise regularly and have no chronic illnesses or musculoskeletal injuries. Participants must avoid alcohol, nicotine products, caffeine, and dietary supplements during the study. Women should have normal menstrual cycles or be on hormonal contraception.

Inclusion Criteria

Body mass index (BMI) between 18.5-30 kg/m2

Healthy without evidence of chronic illness (e.g., diabetes, cardiovascular disease, Crohn's disease) or musculoskeletal injury as determined by the USARIEM Office of Medical Oversight (OMSO) or home duty station medical support

Routinely participate in aerobic and/or resistance exercise at least 2 days per week

Exclusion Criteria

Significantly abnormal blood clotting as determined by OMSO or home duty station medical support

Allergy to lidocaine (or similar local anesthetic)

Present condition of alcoholism, anabolic steroid use, or other substance abuse issues as determined by OMSO or home duty station medical support

Treatment Details

Interventions

• Contralateral active leg (Procedure)
• Unilateral leg immobilization (Procedure)

Trial Overview The study tests how muscle responds to protein intake when one leg is immobilized versus the active other leg in adults. It involves wearing a knee brace for five days and consuming whey protein to examine molecular changes in muscle tissue through blood samples and biopsies.

Participant Groups

Group I: Non-immobilized leg Experimental Treatment 1 Intervention

One leg of a young, healthy adult will remain active and not immobilized for 5 days.

Group II: Immobilized Leg Experimental Treatment 1 Intervention

One leg of a young, healthy adult will be randomly assigned to undergo 5 days of immobilization using a rigid knee brace.

Who Is Running the Clinical Trial?

United States Army Research Institute of Environmental Medicine

Lead Sponsor

Trials

67

Recruited

3,700+

Colonel Sharon Rosser

United States Army Research Institute of Environmental Medicine

Commander

Doctor of Science in PA Studies from Baylor University, Master's in Strategic Studies from Army War College

Dr. Usamah Kayyali

United States Army Research Institute of Environmental Medicine

Senior Science Advisor since 2023

PhD in Toxicology from University of Michigan, Post-doctoral training in Neurobiology at Harvard Medical School