Aging
Conditions
Brief summary
Using stable isotope methodology, investigators will determine the postabsorptive and postprandial muscle protein synthetic response in 60 female adults (Age 50-79, BMI: \<30 kg/m2) immediately after an acute bout of resistance exercise. Participants will be divided in to 5 groups of twelve women (n=12). Each group will receive a different protein beverage or placebo to consume following the resistance exercise training. Group 1 will consume a beverage consisting of whey protein; group 2 will consume whey protein supplemented with additional leucine; group 3 will consume whey protein supplemented with additional leucine and hydrolyzed whey peptides; group 4 will consume whey protein supplemented with additional leucine and citrulline; group 5 will just consume water. During the testing, blood and muscle samples will be collected.
Interventions
BEHAVIORALResistance Exercise
Participants will perform unilateral leg extension exercise immediately prior to ingestion of the experimental beverage
DIETARY_SUPPLEMENT14 g Whey protein
DIETARY_SUPPLEMENT6.6 g Whey protein + 1.25 g leucine
DIETARY_SUPPLEMENT4 g Whey protein + 1.25 g leucine + 2.6 g Whey peptides
DIETARY_SUPPLEMENT6.6 g Whey protein + 1.25 g leucine + 0.8 g Citrulline
OTHERWater control
Sponsors
University of Illinois at Urbana-Champaign
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
FEMALE
Age
20 Years to 79 Years
Healthy volunteers
Yes
Inclusion criteria
* BMI \<30 kg/m2 * Healthy, sedentary * Either 20-30 years old or 50-79 years old
Exclusion criteria
* Tobacco use * Allergies to milk consumption * Unusually high protein consumption * Vegan diet * Allergies to antibiotics or xylocaine * Phenylketonuria (PKU) * Diagnosed GI tract diseases * Arthritic conditions * A history of neuromuscular problems * Heart disease * Metabolic disorders * -Liver, kidney, or urinary disease * Musculoskeletal problems * Autoimmune disease * Neurological disease * Previous participation in amino acid tracer studies * Predisposition to hypertrophic scarring or keloid formation * Individuals on any medications known to affect protein metabolism (i.e. corticosteroids, non-steroidal anti-inflammatories, or prescription strength acne medications). * Individuals using thyroid medications or other medications affecting endocrine function * Pregnancy * Contraindications for exercise * BMI ≥30 * supplements that influence protein metabolism (e.g omega 3 fish oils)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The myofibrillar protein synthetic response to protein ingestion | Postabsorptive for 3 hours, Postprandial for 4 hours hours | Myofibrillar protein synthesis rates will be assessed during the postabsorptive period for 3 hr and during the 4 hr after the ingestion of the experimental beverages. This will allow us to assess the change from the postabsorptive to the postprandial period |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| mTORC1 phosphorylation | Baseline and at 2 and 4 hours after protein ingestion | Activation of anabolic signaling pathways will be assessed in the fasted state and at 2 and 4 hr after the ingestion of the experimental beverages. |
Countries
United States
Outcome results
None listed