Aging, Sarcopenia
Conditions
Keywords
muscle protein synthesis, resistance training, protein supplementation, skeletal muscle physiology, inflammatory cytokines, fecal microbiome, plant protein
Brief summary
This study will evaluate the adaptations in skeletal muscle that occur in response to 10 weeks of weight training with or without peanut protein supplementation in older adult men and women.
Detailed description
Aging is associated with declines in muscle mass, physical strength and physical function. Adequate quality protein intake in aging adults is critical to preventing functional decline. Peanuts provide a unique blend of amino acids that can provide several health benefits to aging adults. While supplementing with peanut protein (PP) powder as part of a resistance training program may increase myofibrillar protein synthesis (i.e., the gold standard molecular assessment in deciphering a muscle-building response), and improve skeletal muscle quality and body composition, no study to date has made this determination. This is a two-phase study using both novel and conventional methods to assess how PP supplementation affects muscle tissue in older individuals who engage in resistance training. These two phases will be conducted as part of a 10-week randomized controlled trial in which men and women aged 50 years and older (n=60), will be stratified by gender and randomized to a resistance training intervention (whole body, two days per week) with PP powder (72g daily; n=15 males, n=15 females) provided during the intervention (immediate group, IG) or after the intervention (wait-list control, WLC, n=15 males, n=15 females). The aims of this study are to determine the acute (deuterium oxide tracer) and chronic (peripheral quantitative computed tomography) effects of PP during resistance training on skeletal muscle myofibrillar protein synthesis rates, changes in skeletal muscle size and quality, changes in whole and appendicular body composition (dual energy x-ray absorptiometry), changes in inflammatory markers and the fecal microbiome.
Interventions
DIETARY_SUPPLEMENTPeanut Protein Powder
Peanut protein powder will be provided to participants who will be instructed to consume 72g daily, mixed with water
BEHAVIORALFull body resistance training
Participants will undergo supervised resistance training two times per week (5 exercises, 3 sets of 8-12 repetitions per set)
Sponsors
Edward Via Virginia College of Osteopathic Medicine
The Peanut Institute
Auburn University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)
Masking description
PI and Co-Is will be blind to participant randomization. One study staff member will be responsible for administering the supplements to participants per randomization
Intervention model description
Intervention group will receive the supplement during the study period and the wait-listed control group will receive the supplement after the study period. Both groups will participate in resistance training during the 10 week period
Eligibility
Sex/Gender
ALL
Age
50 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* body mass index (body mass/height squared) less than 35 kg/m2 * resting blood pressure averaging less than 140/90 mmHg (with or without medication)
Exclusion criteria
* known peanut allergy * actively participating in resistance training for more than 2 days/week * any known overt cardiovascular or metabolic disease * metal implants that will interfere with x-ray procedures * medically necessary radiation exposure in the last six months (except dental x-ray) * any medical condition that would contradict participating in an exercise program, giving blood or donating a skeletal muscle biopsy (i.e. blood clotting disorder or taking blood thinners)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in acute myofibrillar protein synthesis rates | 24 hours | Change in right leg vastus lateralis myofibrillar protein synthesis rates using the integrated deuterium oxide technique from biopsies immediately before and 24 hours after resistance exercise |
| Change in mid-thigh skeletal muscle area and quality | 0-10 weeks | peripheral quantitative computed tomography (pQCT) cross-sectional image of mid-right thigh assessed for total muscle cross-sectional area, subcutaneous adipose tissue area, total intra- and inter-muscular adipose tissue area and overall muscle density |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in leg extensor isokinetic dynamometry | 0-10 weeks | maximal isokinetic right leg extensions on an isokinetic dynamometer (BioDex) |
| Change in whole-body and appendicular body composition | 0-10 weeks | dual energy x-ray absorptiometry (DXA) |
| Change in fecal microbiome composition | 0-10 weeks | alpha- and beta-diversity of 16S bacterial rDNA |
| Change in inflammatory biomarkers | 0-10 weeks | serum C-reactive protein, interleukin-6, tumor necrosis factor-alpha, plasma 8-hydroxy-2'deoxyguanosine |
| Change in Type I and II Muscle Fiber Cross-Sectional Area | 0-10 weeks | Muscle biopsy immunofluorescent staining for determination of type I and type II muscle fiber cross sectional area (fCSA) as a cellular determinant of skeletal muscle hypertrophy |
Countries
United States
Outcome results
None listed