Mitigating Neural Hypoexcitability and Weakness During Disuse in Women

NCT ID: NCT07166198

Last Updated: 2025-09-17

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-11-01
• Study Completion Date: 2026-05-31

Brief Summary

Clinical trial The goal of this clinical trial is to learn how muscle weakness and atrophy develop during short periods of arm immobilization and whether a type of exercise called cross-education can help reduce these effects in women at midlife.

The main questions it aims to answer are:

What changes happen in the nervous system that lead to weakness when a wrist is immobilized?

Can training the opposite arm help maintain muscle strength, muscle size, and nervous system function in the immobilized arm?

Researchers will compare women who have their wrist immobilized with or without opposite-arm resistance training.

Participants will:

Wear a wrist cast on one arm for 7 days

Complete strength training with the opposite arm or no training, depending on their group

Attend study visits for strength and nervous system testing

Have non-invasive tests (like magnetic brain stimulation, muscle recordings, and muscle imaging) to measure how the nervous system and muscle responds

Detailed Description

This clinical trial employs a two-phase, parallel-group randomized controlled design targeting midlife women (ages 40-65), stratified by menopausal status. Participants will be randomized to either a cross-education training group (TRAIN) or a standard care control group (CONTROL).

Phase 1 (Immobilization and Cross-Education Intervention):

To induce rapid declines in neuromuscular function, participants will undergo unilateral wrist immobilization of the non-dominant arm using a hard cast for 7 days. During this period, the TRAIN group will complete three supervised resistance training sessions with the non-immobilized arm, while the CONTROL group will remain inactive. The intervention protocol emphasizes eccentric-biased resistance exercise, as prior data indicate that eccentric contractions optimize neural adaptation and mechanical loading. The protocol was developed from prior laboratory work and proof-of-concept interventions, with the goal of maximizing the cross-education response.

Phase 2 (Rehabilitation and Recovery):

Following cast removal, both groups will complete a 2-week standardized rehabilitation program (3 sessions per week) designed to restore wrist strength and function in the previously immobilized arm. Rehabilitation training is supervised and includes progressive resistance exercise to target recovery of neuromuscular performance.

Conditions

Muscle Weakness

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: SINGLE

Study Groups

Intervention Group (TRAIN)

This group will receive the experimental intervention

Group Type: EXPERIMENTAL

Wrist immobilization

Intervention Type: DEVICE

The wrist immobilization will use a medical device (wrist cast) to immobilize the left, non-dominant wrist for 7 days.

Resistance training

Intervention Type: BEHAVIORAL

The cross-education intervention will consist of resistance training on the dominant, right hand.

Resistance training rehabilitation

Intervention Type: BEHAVIORAL

The resistance training rehabilitation will occur for the non-dominant, left hand following the immobilization phase for all participants.

Control Group (CON)

This group will not receive the experimental intervention

Group Type: ACTIVE_COMPARATOR

Wrist immobilization

Intervention Type: DEVICE

The wrist immobilization will use a medical device (wrist cast) to immobilize the left, non-dominant wrist for 7 days.

Resistance training rehabilitation

Intervention Type: BEHAVIORAL

The resistance training rehabilitation will occur for the non-dominant, left hand following the immobilization phase for all participants.

Interventions

Wrist immobilization

The wrist immobilization will use a medical device (wrist cast) to immobilize the left, non-dominant wrist for 7 days.

Intervention Type: DEVICE

Resistance training

The cross-education intervention will consist of resistance training on the dominant, right hand.

Intervention Type: BEHAVIORAL

Resistance training rehabilitation

The resistance training rehabilitation will occur for the non-dominant, left hand following the immobilization phase for all participants.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Women between 40-65 years of age
• Baseline handgrip strength >20Kg
• Right-hand dominant

Exclusion Criteria

• Personal or family history of blood clots
• Current use of anticoagulant medications
• Neuromuscular or metabolic diseases (e.g., multiple sclerosis, diabetes)
• Arthritis
• Osteoporosis or osteopenia
• History of myocardial infarction within the past year
• Chronic pain ≥3/10 for ≥3 months
• Uncontrolled hypertension (≥140/90 mmHg)
• Upper extremity surgery within the past year
• Use of assistive hand or arm device within the past year
• Fall involving the upper extremities within the past year
• Upper extremity injuries preventing safe participation
• Use of body composition-altering medications (e.g., testosterone, GLP-1 agonists) in past 6 months
• Current use of muscle relaxants, benzodiazepines, or similar drugs
• Smoking within the past 6 months
• History of drug or alcohol abuse within the past year
• Severe anxiety or claustrophobia
• Pregnancy (current or planned)
• Allergies to medical adhesives
• High risk of sarcopenia (per SARC-F)
• Contraindications to TMS or MRI
• Not right-hand dominant
• Upper-body resistance training within the past 6 months
• Inability/unwillingness to refrain from resistance training during study

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

National Institute of General Medical Sciences (NIGMS)

NIH

Sponsor Role: collaborator

Kansas State University

OTHER

Sponsor Role: lead

Responsible Party

Joshua Carr

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Joshua Carr, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

Kansas State University

Locations

Neuromuscular Physiology Laboratory

Manhattan, Kansas, United States

Countries

United States

Central Contacts

Joshua Carr, Ph.D.

Role: CONTACT

joshuacarr@ksu.edu

785-532-0700

Julio Hernandez-Pavon, Ph.D.

Role: CONTACT

juliohpavon@ksu.edu

Other Identifiers

5P20GM113109-09

Identifier Type: NIH

Identifier Source: secondary_id

View Link

12503

Identifier Type: -

Identifier Source: org_study_id