Neural Mechanisms of Dynapenia
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Aging
- Sponsor
- Ohio University
- Enrollment
- 89
- Locations
- 1
- Primary Endpoint
- Motor cortical excitability
- Status
- Completed
- Last Updated
- 7 years ago
Overview
Brief Summary
The UNCODE Study seeks to better identify the neurological causes of muscle weakness associated with advancing age. The main study consists of 4 laboratory-based testing sessions that involve testing muscle strength and physical and cognitive function as well as a battery of tests to 1) quantify brain excitability (using non-invasive transcranial magnetic stimulation), 2) modulate brain excitability (using non-invasive transcranial direct current stimulation), 3) spinal motor nerve firing characteristics, and 4) brain structure and function characteristics based on magnetic resonance images of the brain. Additionally, three option sub-studies are also available for enrollment. The first is a genetics sub-study where a cheek swab will be used to examine associations between certain genes and the physiological and functional measures obtained from the main study. The other two sub-studies are interventions. The first sub-study is a progressive resistance exercise training study where study participants will undergo 12-weeks of exercise training (3x/wk) and at the completion of the exercise training the measures obtained in the main study will be re-assessed. The other sub-study is a mental imagery sub-study where subjects are randomly assigned to perform a mental imagery training program consisting of imaging strong muscle contractions and mobility tasks (5x/wk) or to serve as a control (i.e., to not modify lifestyle) for 6-weeks. At the completion of the respective intervention period the measures obtained in the main study will be re-assessed.
Detailed Description
The UNCODE Study seeks to better identify the neurological causes of muscle weakness associated with advancing age. The main study consists of 4 laboratory-based testing sessions that involve testing muscle strength and physical and cognitive function as well as a battery of tests to 1) quantify brain excitability (using single and paired pulse transcranial magnetic stimulation of the upper and lower extremity muscles), 2) modulate brain excitability of the upper extremity muscles (using non-invasive transcranial direct current stimulation), 3) spinal motor nerve firing characteristics using decomposition surface electromyography, and 4) brain structure and function characteristics based on magnetic resonance images of the brain. Additionally, three optional sub-studies are also available for enrollment. The first is a genetics sub-study where a cheek swab will be used to examine associations between certain genes (APOE-4 allele) and the physiological and functional measures obtained from the main study. The other two sub-studies are interventions. The first sub-study is a progressive resistance exercise training study where study participants will undergo 12-weeks of exercise training (3x/wk) and at the completion of the exercise training the measures obtained in the main study will be re-assessed. The other sub-study is a mental imagery sub-study where subjects are randomly assigned to perform a mental imagery training program consisting of imaging strong muscle contractions and mobility tasks (5x/wk) or to serve as a control (i.e., to not modify lifestyle) for 6-weeks. At the completion of the respective intervention period the measures obtained in the main study will be re-assessed.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Age 60+ years with no significant health issues or conditions that, in the investigator's opinion, would limit the subject's ability to complete the study per protocol or that would impact the capability to get an accurate measurement of study endpoints.
- •Body mass index between 16.0 and 40.0 kg/m
- •With no condition that would limit participation in supervised resistance training exercise based on the Physical Activity Readiness Questionnaire (PAR-Q) (for the "Resistance Exercise Training Sub-Study only).
- •Willingness to maintain current diet and adhere to the intervention programs described for the sub-studies (if applicable) and willing to undergo all testing procedures.
- •Able to read, understand, and complete study-related questionnaires
- •Able to read and understand, and willing to sign the informed consent form (ICF).
Exclusion Criteria
- •Failure to provide informed consent.
- •Any activity of daily living (ADL) disability (difficulty feeding, dressing, continence, bathing, toileting, and transferring).
- •Lives in a nursing home; persons living in assisted or independent housing will not be excluded.
- •Cognitive impairment, defined as a known diagnosis of dementia or Modified Mini-Mental State exam score \<24
- •Known neuromuscular or neurological conditions affecting somatosensory or motor function or control (e.g., hemiplegia, multiple sclerosis, peripheral neuropathy, Parkinson's disease, Myasthenia Gravis, Ataxia, Apraxia, post-polio syndrome, mitochondrial myopathy, etc.).
- •Unable to communicate because of severe hearing loss or speech disorder.
- •Severe visual impairment, which would preclude completion of the assessments.
- •Cancer requiring treatment currently or in the past 2 years (except primary non-melanoma skin cancer or in situ cervical cancer)
- •Hospitalization (medical confinement for ≥24 hours), or immobilization, or major surgical procedure requiring general anesthesia within 12 weeks prior to screening, or any planned surgical procedures during the study period.
- •Chronic or relapsing/remitting gastrointestinal disorders such as inflammatory bowel disease and irritable bowel syndrome.
Outcomes
Primary Outcomes
Motor cortical excitability
Time Frame: Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.
Obtained using transcranial magnetic stimulation
Voluntary activation
Time Frame: Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.
Obtained based an the ratio of voluntary to electrically stimulated muscle forces
Secondary Outcomes
- Memory(Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.)
- Motor unit discharge characteristics(Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.)
- White matter hyper intensities(Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.)
- Stair climb power(Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.)
- Motor jerkiness(Change from baseline measure after 12-weeks for resistance exercise group and 6-weeks for mental imagery and control groups.)