Muscle Disuse Atrophy
Conditions
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.
Interventions
PROCEDUREOrthopedic immobilization
Orthopedic immobilization will be performed with a sling and swathe.
Unilateral resistance training will be performed by the dominant arm of the immobilization + unilateral resistance training group during Phase 1.
Bilateral resistance training will be performed by both arms in both groups during Phase 2.
Sponsors
Texas Christian University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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 |
Countries
United States
Outcome results
None listed