Skeletal Muscle Myosin Binding Protein C in Fatigue and Aging
University of Oregon
Summary
This study is investigating changes to the proteins in skeletal muscle that contribute to reduced muscle size and muscle function that occurs with aging.
Description
Age-related muscle atrophy and contractile dysfunction have been well described at the cellular level, but the molecular mechanisms that contribute to this dysfunction are poorly understood. Improved understanding of these mechanisms is critically important for the improvement of physical rehabilitation in older adults at risk for mobility impairment and physical disability. Our studies will pursue pre-clinical evidence that post translational modification of specific proteins in skeletal muscle lead to an "aging phenotype" in skeletal muscle that may unlock new strategies for improving physic…
Eligibility
- Age range
- 18–80 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Adults between the ages 18-35 or 65-80 years * Healthy by self-report * Willing to participate in all aspects of the study design including muscle biopsy, unilateral exercise, and physical activity monitoring * Fluent in English (due to lack of translation services, it is not practical to conduct the study using a language other than English). Exclusion Criteria: * Orthopaedic limitation (severe knee osteoarthritis, prior joint replacement, etc.). * Volunteer has dementia or related mental issues that potentially put the subject at risk as determined by prior diagnosis…
Interventions
- BehavioralFatiguing Exercise
Volunteers will perform knee extension exercise of the dominant limb while seated in a chair designed for exercise of the knee extensor muscle group. The chair will be equipped with a lever arm, aligned with the axis of rotation of the knee and fixed to the distal shank, 2 centimeters proximal to the ankle joint. The lever arm will be instrumented to provide resistance and measure velocity. The volunteers will perform 3-5 maximum voluntary contractions (MVC) to determine peak torque. Once established, volunteers will rest for 5 minutes before initiating the fatigue protocol, whereby they will perform repeated MVC of the dominant limb against resistance equal to or less than 50% of MVC until range of motion cannot be maintained. Because the goal of this exercise is to uniformly fatigue the quadriceps muscle group, this exercise will be performed continuously. It is expected to take between 1 and 3 minutes to achieve the desired level of fatigue.
Location
- University of OregonEugene, Oregon