---
title: Brain and Muscle Plasticity During Immobilization
nct_id: NCT05115643
overall_status: COMPLETED
phase: NA
sponsor: McGill University
study_type: INTERVENTIONAL
primary_condition: Muscle Atrophy
countries: Canada
canonical_url: "https://parkinsonspathways.com/agent/trials/NCT05115643.md"
clinicaltrials_gov: "https://clinicaltrials.gov/study/NCT05115643"
ct_last_update_post_date: 2022-05-19
last_seen_at: "2026-05-12T07:34:28.885Z"
source: ClinicalTrials.gov (mirrored, no enrichment)
---
# Brain and Muscle Plasticity During Immobilization

**Official Title:** Examining Changes in Muscle Size and Strength, Neuromuscular Function, and Brain Plasticity During Limb Immobilization in Women

**NCT ID:** [NCT05115643](https://clinicaltrials.gov/study/NCT05115643)

## Key Facts

- **Status:** COMPLETED
- **Phase:** NA
- **Study Type:** INTERVENTIONAL
- **Target Enrollment:** 12
- **Lead Sponsor:** McGill University
- **Conditions:** Muscle Atrophy
- **Start Date:** 2021-10-08
- **Completion Date:** 2022-04-21
- **CT.gov Last Update:** 2022-05-19

## Brief Summary

Patients in rehabilitation may undergo periods of prolonged limb immobilization in response to injury, surgery, or illness. Due to disuse, the size and strength of muscles controlling the affected limb can decrease significantly, possibly resulting in physical impairment or lower quality of life during the recovery phase. Prior immobilization studies have shown that the rate and degree of decline in muscle strength exceeds that of muscle size, indicating that determinants of muscle strength unrelated to muscle size may further contribute to functional changes during immobilization.

The purpose of this study is to describe the changes in muscle strength, muscle size, corticospinal excitability, voluntary activation, M1 cortical thickness, and resting state functional connectivity following a 2-week limb immobilization period in young women.

## Eligibility

- **Minimum age:** 18 Years
- **Maximum age:** 35 Years
- **Sex:** FEMALE
- **Healthy Volunteers:** Yes

```
Inclusion Criteria:

* Biologically female
* Right-hand dominant
* Body mass index between 18.5-30 kg/m\^2 (inclusive)
* Regular menstrual cycle
* Be able to maintain a habitual diet throughout the duration of the study

Exclusion Criteria:

* Use of tobacco
* Pregnancy
* A history of brain trauma
* Suffers from a neurological disease or movement disorder
* Peripheral nerve damage
* Use of medications known to affect protein metabolism (i.e., corticosteroids, non-steroidal anti-inflammatory drugs, or prescription strength acne medications)
* Diagnosed with or suspects having a psychiatric illness
* Use of dietary supplements known to affect muscle size (i.e., creatine, fish oil)
* Past or present diagnosis of an eating disorder by a physician or registered dietician
* Possesses any metal implants (e.g. artificial joints, pacemakers, stents) or non-removeable medical devices that are contraindicative for magnetic resonance imaging (e.g. insulin pumps)
```

## Arms

- **Immobilized arm** (EXPERIMENTAL) — Left arm of participant
- **Non-immobilized arm** (NO_INTERVENTION) — Right arm of participant

## Interventions

- **Immobilization** (BEHAVIORAL) — Immobilization of left arm using a brace and sling.

## Primary Outcomes

- **Change in isometric elbow flexion and extension peak torque, both arms** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_ — Measured using an isokinetic dynamometer; peak torque during static contraction of the elbow flexors and extensors
- **Change in isokinetic elbow flexion and extension peak torque, both arms** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_ — Measured using an isokinetic dynamometer; peak torque during dynamic contraction of the elbow flexors and extensors
- **Change in cross-sectional area of the elbow flexor and extensor muscles, both arms** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_ — Obtained from magnetic resonance images of each arm
- **Change in volume of the elbow flexor and extensor muscles, both arms** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_ — Obtained from magnetic resonance images of each arm
- **Voluntary activation of biceps brachii, both arms** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_ — Measured using peripheral nerve stimulation and an isokinetic dynamometer; estimation of the capacity to voluntarily activate the force-generating elements of the biceps brachii during maximal effort elbow flexion
- **Change in corticospinal excitability of biceps brachii, both arms** _(time frame: Comparison between before immobilization and 24 hours of left arm immobilization, and before and after 2 weeks of left arm immobilization)_ — Measured using transcranial magnetic stimulation; estimation of the efficacy of the corticospinal tract to relay electrical signals to the biceps brachii muscle

## Secondary Outcomes

- **Change in right and left primary motor cortex thickness** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_
- **Change in whole brain resting state functional connectivity** _(time frame: Comparison between before and after 2 weeks of left arm immobilization)_

## Locations (1)

- Exercise Metabolism and Nutrition Research Laboratory, Montreal, Quebec, Canada

## Recent Field Changes (last 30 days)

- `status.overallStatus` — added _(2026-05-12)_
- `status.primaryCompletionDate` — added _(2026-05-12)_
- `status.completionDate` — added _(2026-05-12)_
- `status.lastUpdatePostDate` — added _(2026-05-12)_
- `design.phases` — added _(2026-05-12)_
- `design.enrollmentCount` — added _(2026-05-12)_
- `eligibility.criteria` — added _(2026-05-12)_
- `eligibility.minAge` — added _(2026-05-12)_
- `eligibility.maxAge` — added _(2026-05-12)_
- `eligibility.sex` — added _(2026-05-12)_
- `outcomes.primary` — added _(2026-05-12)_
- `outcomes.secondary` — added _(2026-05-12)_
- `armsInterventions.arms` — added _(2026-05-12)_
- `armsInterventions.interventions` — added _(2026-05-12)_
- `sponsor.lead` — added _(2026-05-12)_
- `results.hasResults` — added _(2026-05-12)_
- `locations.exercise metabolism and nutrition research laboratory|montreal|quebec|canada` — added _(2026-05-12)_

---

*Canonical: https://parkinsonspathways.com/agent/trials/NCT05115643.md*  
*Source data (authoritative): https://clinicaltrials.gov/study/NCT05115643*  
*This page is a raw mirror with no AI summary, no editorial enrichment, and no Parkinson's-specific filtering.*