Nutritional Strategies to Augment the Postprandial Muscle Protein Synthetic Response to the Ingestion of a Low Dose of Protein in Middle-aged Women

Not Applicable

Completed

• Conditions: Aging
• Interventions: Behavioral: Resistance Exercise; Dietary Supplement: 4 g Whey protein + 1.25 g leucine + 2.6 g Whey peptides; Dietary Supplement: 6.6 g Whey protein + 1.25 g leucine + 0.8 g Citrulline; Dietary Supplement: 14 g Whey protein; Dietary Supplement: 6.6 g Whey protein + 1.25 g leucine; Other: Water control

• Registration Number: NCT02918981
• Lead Sponsor: University of Illinois at Urbana-Champaign

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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2016-09-20
• Study First Submitted QC: 2016-09-27
• Study First Posted: 2016-09-29
• Study Start: 2016-10
• Primary Completion: 2019-03-06
• Study Completion: 2019-03-06
• Status Verified: 2020-11
• Last Update Submitted: 2020-11-02
• Last Update Posted: 2020-11-03

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 50

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)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Whey protein	Resistance Exercise	After resistance exercise, participants aged 50-79 years will consume 14g Whey protein dissolved in 200 mL of water
Whey + Leucine + Whey peptides	4 g Whey protein + 1.25 g leucine + 2.6 g Whey peptides	After resistance exercise, participants aged 50-79 years will consume 4 g Whey protein + 1.25 g Leucine + 2.6 g Whey peptides dissolved in 200 mL of water
Whey + Leucine + Citrulline	6.6 g Whey protein + 1.25 g leucine + 0.8 g Citrulline	After resistance exercise, participants aged 50-79 years will consume 6.6 g Whey protein + 1.25 g Leucine + 0.8 g Citrulline dissolved in 200 mL of water
Whey protein	14 g Whey protein	After resistance exercise, participants aged 50-79 years will consume 14g Whey protein dissolved in 200 mL of water
Whey + Leucine	6.6 g Whey protein + 1.25 g leucine	After resistance exercise, participants aged 50-79 years will consume 6.6 g Whey protein + 1.25 g Leucine dissolved in 200 mL of water
Whey + Leucine + Whey peptides	Resistance Exercise	After resistance exercise, participants aged 50-79 years will consume 4 g Whey protein + 1.25 g Leucine + 2.6 g Whey peptides dissolved in 200 mL of water
Water	Water control	After resistance exercise, participants aged either 20-30 or 50-79 years old will consume 200 mL water
Whey + Leucine	Resistance Exercise	After resistance exercise, participants aged 50-79 years will consume 6.6 g Whey protein + 1.25 g Leucine dissolved in 200 mL of water
Whey + Leucine + Citrulline	Resistance Exercise	After resistance exercise, participants aged 50-79 years will consume 6.6 g Whey protein + 1.25 g Leucine + 0.8 g Citrulline dissolved in 200 mL of water
Water	Resistance Exercise	After resistance exercise, participants aged either 20-30 or 50-79 years old will consume 200 mL water

Primary Outcome Measures

Name	Time	Method
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 Outcome Measures

Name	Time	Method
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.

Trial Locations

Locations (1)

Freer Hall; 🇺🇸 Urbana, Illinois, United States