Independent and Combined Effects of Resistance Exercise Training and β-hydroxy β-methylbutyrate Plus Vitamin D on Body Composition and Skeletal Muscle Health
Overview
- Phase
- N/A
- Intervention
- Not specified
- Conditions
- Aging
- Sponsor
- University of Illinois at Urbana-Champaign
- Enrollment
- 48
- Locations
- 1
- Primary Endpoint
- Skeletal Muscle Function - Knee extensor isokinetic performance
- Last Updated
- 6 years ago
Overview
Brief Summary
During middle-age, humans begin to lose muscle mass and strength. With increasing age the deterioration of muscle health is associated with a decline in quality of life and the loss of independence. β-hydroxy β-methylbutyrate (HMB) plus Vitamin D (VitD) have been proposed to increase skeletal muscle mass, contractile function and improve body composition but has yet to be evaluated in middle-aged women. The overall goal of this study is to determine the effects of HMB +VitD supplementation during 12 weeks of resistance exercise training or a non-exercise control on body composition, skeletal muscle size, and skeletal muscle function in middle-aged women.
Detailed Description
To determine if HMB+VitD supplementation is an effective strategy to help prevent the loss of skeletal muscle size, skeletal muscle function and body composition in middle-aged women, forty eight women (45-60 yrs old) will be recruited to complete a 12-week intervention (n=12 per group; 4 groups). Participants will be randomized to complete a non-exercise control period or a resistance exercise training program. In a double-blinded fashion, participants in the non-exercise or resistance exercise groups will be randomized to consume either placebo or HMB+VitD. Before and after each intervention the investigators will evaluate skeletal muscle size, skeletal muscle function, and body composition.
Investigators
Adam Konopka
Assistant Professor
University of Illinois at Urbana-Champaign
Eligibility Criteria
Inclusion Criteria
- •Women between 45 and 60 years old
- •Women with a BMI \< 35 kg/m2
- •Sedentary (\< 30 minutes of structured physical activity 3 times per week)
- •Weight stable for 3 months prior (+/- 5kg)
Exclusion Criteria
- •Body mass index \> 35 kg/m2
- •Type 1 or Type 2 diabetes
- •Uncontrolled hypertension
- •Active cancer, cancer in remission, or having received treatment for any form of cancer in the previous 5 years
- •Cardiovascular disease (e.g., peripheral artery disease and peripheral vascular disease)
- •Uncontrolled thyroid function
- •Chronic and/or regular consumption of medication known to influence skeletal muscle metabolism
- •Use of Vitamin D (\>2000 IU) or β-hydroxy β-methylbutyrate
- •Tobacco use
- •Any condition that limits exercise training (e.g., chronic obstructive pulmonary disease, neuromuscular disorder, moderate or severe cognitive impairment, Alzheimer's disease, vertigo, dizziness)
Outcomes
Primary Outcomes
Skeletal Muscle Function - Knee extensor isokinetic performance
Time Frame: Change from baseline to after the 12 week intervention
Knee extensor isokinetic performance will be assessed by a dynamometer.
Skeletal Muscle Function - Fatigue
Time Frame: Change from baseline to after the 12 week intervention
Knee extensor fatigue will be assessed by a dynamometer.
Skeletal Muscle Function - Knee extensor isometric performance
Time Frame: Change from baseline to after the 12 week intervention
Knee extensor isometric performance will be assessed by a dynamometer. Muscle strength will also be determined by 1 repetition maximum for leg extension, leg curl and leg press exercises.
Skeletal Muscle Cross Sectional Area
Time Frame: Change from baseline to after the 12 week intervention
Skeletal muscle cross sectional area will be assessed via magnetic resonance imaging (MRI).
Body Composition - Percentage
Time Frame: Change from baseline to after the 12 week intervention
Fat and fat free percent will be measured using by a dual x-ray absorptiometry (DEXA) scan.
Skeletal Muscle Mitochondrial Respiration
Time Frame: Change from baseline to after the 12 week intervention
Mitochondrial respiration will be assessed using high-resolution respirometry in permeabilized muscle fibers.
Body Composition - Mass
Time Frame: Change from baseline to after the 12 week intervention
Fat and fat free mass will be measured using by a dual x-ray absorptiometry (DEXA) scan.
Skeletal Muscle Volume
Time Frame: Change from baseline to after the 12 week intervention
Skeletal muscle volume will be assessed via magnetic resonance imaging (MRI).
Myofiber Size
Time Frame: Change from baseline to after the 12 week intervention
Cross sectional area of muscle fibers will be evaluated with immunohistochemistry.
Skeletal Muscle Mitochondrial Hydrogen Peroxide Emissions
Time Frame: Change from baseline to after the 12 week intervention
Mitochondrial hydrogen peroxide emissions will be assessed using high-resolution fluorometry in permeabilized muscle fibers.
Secondary Outcomes
- Bone Density(Change from baseline to after the 12 week intervention)