Strength Training Augmenting Rehabilitation

Not Applicable

• Conditions: Muscle Disuse Atrophy
• Interventions: Procedure: Orthopedic immobilization; Other: Bilateral resistance training; Other: Unilateral resistance training

• Registration Number: NCT05097092
• Lead Sponsor: Texas Christian University

Brief Summary

This project aims to determine whether a novel strength training rehabilitation protocol can diminish the negative consequences of limb immobilization and expedite the restoration of muscle function during retraining in healthy individuals.

Detailed Description

The present study will examine the time course of muscle strength and size adaptations in two groups of volunteers during immobilization and retraining. Both groups will undergo temporary muscle disuse by wearing a shoulder sling and swathe on their non-dominant arm for \~≥10 hours/day for four weeks. One group (immobilization + unilateral training) will perform progressive unilateral strength training of the free limb throughout the immobilization period. The other group (immobilization control) will not undergo any training during the immobilization period. Following immobilization, both groups will undergo four weeks of bilateral strength training to retrain the immobilized arm.

Study Timeline

• Study Start: 2021-08-13
• Study First Submitted: 2021-09-22
• Status Verified: 2021-10
• Study First Submitted QC: 2021-10-14
• Last Update Submitted: 2021-10-14
• Study First Posted: 2021-10-27
• Last Update Posted: 2021-10-27
• Primary Completion: 2023-08-13
• Study Completion: 2023-08-14

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• a body mass index between 18 - 35 kg/m2
• 18-35 years of age
• right-hand dominant
• willingness to comply with the immobilization requirements
• willingness to refrain from strength training outside of the study
• willingness to comply with the strength training procedures of the study

Exclusion Criteria

• a personal or family history of blood clots
• a personal or family history of thyroid disorders
• previous orthopedic surgeries to the upper limbs and/or joint pain of the upper limbs in the last 6 months
• neuromuscular or metabolic disorders
• osteoarthritis
• use of hormone replacement therapy (ie., testosterone, estrogen, and/or growth hormone pharmaceuticals)
• pregnancy and/or nursing

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Immobilization control	Bilateral resistance training	The immobilization control group will undergo arm immobilization. Immobilization will be implemented with four weeks of muscle unloading with a sling and swathe on the nondominant arm. The sling will suspend the arm at the elbow joint with the elbow in a flexed position at 90°, the swathe will then wrap around the participant to fix the arm against the body.
Immobilization control	Orthopedic immobilization	The immobilization control group will undergo arm immobilization. Immobilization will be implemented with four weeks of muscle unloading with a sling and swathe on the nondominant arm. The sling will suspend the arm at the elbow joint with the elbow in a flexed position at 90°, the swathe will then wrap around the participant to fix the arm against the body.
Immobilization with unilateral training	Orthopedic immobilization	The immobilization with unilateral training group will undergo arm immobilization for four with a sling and swathe on the nondominant arm. The sling will suspend the arm at the elbow joint with the elbow in a flexed position at 90°, the swathe will then wrap around the participant to fix the arm against the body. The free (non-immobilzed) arm of this group will undergo heavy strength training twice per week throughout the immobilization period. The training will consist of unilateral dumbbell shoulder press and biceps curl.
Immobilization with unilateral training	Unilateral resistance training	The immobilization with unilateral training group will undergo arm immobilization for four with a sling and swathe on the nondominant arm. The sling will suspend the arm at the elbow joint with the elbow in a flexed position at 90°, the swathe will then wrap around the participant to fix the arm against the body. The free (non-immobilzed) arm of this group will undergo heavy strength training twice per week throughout the immobilization period. The training will consist of unilateral dumbbell shoulder press and biceps curl.
Immobilization with unilateral training	Bilateral resistance training	The immobilization with unilateral training group will undergo arm immobilization for four with a sling and swathe on the nondominant arm. The sling will suspend the arm at the elbow joint with the elbow in a flexed position at 90°, the swathe will then wrap around the participant to fix the arm against the body. The free (non-immobilzed) arm of this group will undergo heavy strength training twice per week throughout the immobilization period. The training will consist of unilateral dumbbell shoulder press and biceps curl.

Primary Outcome Measures

Name	Time	Method
Changes in isometric muscle strength	Changes from baseline at 5 and 10 weeks	MVC (Newton)
Changes in dynamic muscle strength	Changes from baseline at 5 and 10 weeks	1RM (lbs)
Changes in muscle size	Changes from baseline at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 weeks	Ultrasound muscle thickness of biceps brachii and triceps brachii
Changes in lean mass	Changes from baseline at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 weeks	DEXA
Changes in EMG amplitude	Changes from baseline at 5 and 10 weeks	Surface EMG
Changes in action potential amplitude	Changes from baseline at 5 and 10 weeks	Surface EMG Decomposition

Trial Locations

Locations (2)

TCU Neuromuscular Physiology Laboratory; 🇺🇸 Fort Worth, Texas, United States

TCU RIC; 🇺🇸 Fort Worth, Texas, United States