Bedrest for Muscle Atrophy

(FABRIC Trial)

Overseen By Chris McGlory, PhD.

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Queen's University

Must not be taking: Insulin, Anticoagulants, Anabolic hormones

Disqualifiers: Cardiovascular, Metabolic, Neuromuscular, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

12 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how bedrest affects muscles in healthy young adults. Researchers aim to determine changes in muscle size, strength, and endurance when participants remain in bed for five days. They also examine how the body manages insulin (a hormone that controls blood sugar) and how muscles produce energy during this period. This trial suits generally healthy adults aged 18-30 who exercise recreationally and maintain a stable body weight. As an unphased study, it offers a unique opportunity to contribute to the scientific understanding of muscle health and energy use.

Will I have to stop taking my current medications?

The trial requires that you do not use medications that affect muscle protein turnover or anticoagulant medications. If you are on such medications, you may need to stop taking them to participate.

What prior data suggests that bedrest is safe for healthy, young adults?

Research shows that short-term bedrest, such as five days, is usually safe for healthy individuals. Studies have found that staying in bed can lead to muscle weakness, which can start quickly, sometimes within just a few days. However, these changes are usually temporary and reversible. For example, muscle shrinking and weakness have appeared in various studies, but participants did not experience serious problems during these rest periods.

While losing some muscle and strength is common, these effects are generally not harmful in the short term for healthy adults. The body typically returns to normal once regular activities resume. Overall, when properly monitored, bedrest in these trials is considered safe for participants. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the bedrest protocol for muscle atrophy because it offers a unique way to understand how strict inactivity impacts muscles over a short time. Unlike other treatments that might involve physical therapy or medications targeting muscle preservation, this approach provides a controlled environment to observe muscle changes and recovery. By monitoring diet and activity closely, researchers hope to uncover insights into muscle deterioration and recovery, potentially leading to new strategies for preventing or reversing muscle loss.

What evidence suggests that bedrest is effective for studying muscle atrophy?

Research has shown that staying in bed can quickly weaken muscles and cause them to shrink. One study found that after just five days of bedrest, both young and older adults lost 9–14% of their muscle strength. Another study found that one week of bedrest significantly reduced muscle size and made it harder for the body to use insulin to control blood sugar. These findings suggest that even short periods of bedrest can lead to noticeable muscle loss and affect how the body handles sugar. Participants in this trial will undergo a 19-day study period, including 5 days of strict bedrest, to further investigate these effects. ^{1 2 6 7 8}

Who Is on the Research Team?

Chris McGlory, PhD.

Principal Investigator

Queen's University

Are You a Good Fit for This Trial?

This trial is for healthy, young adults interested in how bedrest affects muscle and insulin response. Participants must be willing to undergo MRI scans, strength tests, glucose oxidation studies, muscle biopsies, and blood sampling before and after a control period and 5 days of strict bedrest.

Inclusion Criteria

Generally healthy as assessed by medical and physical activity questionnaires

BMI between 18.5-28 kg/m2

Weight stable (within ±2kg for 6 months)

Exclusion Criteria

My BMI is either below 18.5 or above 28.

I use insulin to manage my blood sugar.

I have a history of heart, lung, metabolic, muscle, or bone diseases.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline Control

Participants undergo baseline testing and a free-living control period with habitual daily activities

5 days

Baseline testing visits

Bedrest

Participants undergo 5 days of strict horizontal bedrest with controlled diet and monitored physical activity

5 days

Pre and post bedrest testing visits

Follow-up

Participants are monitored for changes in muscle mass, strength, and metabolic function after bedrest

2 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Bedrest

Trial Overview The study investigates the impact of 5 days of complete bedrest on muscle volume, strength, fatigue resistance, whole-body insulin sensitivity, mitochondrial function, and protein synthesis in skeletal muscles using various medical tests.

How Is the Trial Designed?

Group I: Experimental: Bedrest Experimental Treatment 1 Intervention

19 day study period, consisting of baseline testing, 5 days of free-living (habitual daily activities) immediately followed by 5 days of strict bedrest. Diet controlled and physical activity monitored for entire study period.

Who Is Running the Clinical Trial?

Queen's University

Lead Sponsor

Trials

382

Recruited

122,000+

Canadian Institutes of Health Research (CIHR)

Collaborator

Trials

1,417

Recruited

26,550,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8325614/

Nonuniform loss of muscle strength and atrophy during bed rest Over the first 2 wk of bed rest, the decline in muscle strength is much faster than that of muscle atrophy, it reaches a maximum of 4.2 on the 5th day, falling ...

2. diabetesjournals.org diabetesjournals.org/diabetes/article/65/10/2862/35009/One-Week-of-Bed-Rest-Leads-to-Substantial-Muscle

One Week of Bed Rest Leads to Substantial Muscle Atrophy ... In conclusion, 1 week of bed rest substantially reduces skeletal muscle mass and lowers whole-body insulin sensitivity, without affecting ...

3. physoc.onlinelibrary.wiley.com physoc.onlinelibrary.wiley.com/doi/10.14814/phy2.16166

Five days of bed rest in young and old adults: Retainment of ... In the present study, maximal voluntary muscle strength decreased by ~9–14% following 5 days of bed rest in both NMES and CON conditions ...

4. frontiersin.org frontiersin.org/journals/nutrition/articles/10.3389/fnut.2021.633987/full

The Aging Muscle in Experimental Bed Rest: A Systematic ... Overall, total lean body mass was decreased by 1.5 kg, while there was no relationship between bed rest duration and outcomes (Z = 0.423, p = 672). The meta- ...

5. journals.lww.com journals.lww.com/ccejournal/fulltext/2020/12000/disuse_induced_muscle_loss_and_rehabilitation__the.7.aspx

Disuse-Induced Muscle Loss and Rehabilitation Conclusions: Bed rest results in upper and lower leg muscle atrophy in a linear pattern, and an 11-day rehabilitation program was safe and effective in ...

6. extremephysiolmed.biomedcentral.com extremephysiolmed.biomedcentral.com/articles/10.1186/s13728-015-0036-7

The impact of extended bed rest on the musculoskeletal ... Bed rest and microgravity. The most commonly used model, bed rest has been shown to cause muscle wasting within 10 days in healthy older adults ...

7. clinicaltrials.gov clinicaltrials.gov/study/NCT02694471

Effect of 14 Day Bed Rest on Health Outcomes in Young ... Greater loss in muscle mass and function but smaller metabolic alterations in older compared with younger men following 2 wk of bed rest and recovery. J ...

8. physio-pedia.com physio-pedia.com/Bed_Rest_And_Skeletal_Muscle

Bed Rest And Skeletal Muscle Muscle atrophy (sarcopenia) and muscle strength losses occur very quickly with prolonged bed rest. Hospitalization of ≤5 days, referring to disuse/ ...