Assessing the Impact of "Super-whey" vs. Isonitrogenous Whey on Muscle Protein Synthesis

Not Applicable

Completed

• Conditions: Sarcopenia
• Interventions: Dietary Supplement: Isonitrogenous whey protein; Dietary Supplement: Super-Whey protein

• Registration Number: NCT05701202
• Lead Sponsor: University of Nottingham

Brief Summary

Skeletal muscle accounts for approximately 45-55% of total body mass in healthy adults and plays a pivotal role in whole-body metabolic health, locomotion and physical independence. Undesirable loss of skeletal muscle mass (atrophy) is, however, a common feature of many diseases and scenarios including ageing, bed rest/immobilisation, cancer and physical inactivity. Despite the exact mechanisms causing muscle atrophy being not yet fully understood, "anabolic resistance" (reduced muscle building in response to protein feeding and exercise) is thought to be key, especially for age-related skeletal muscle losses (known as sarcopenia). As such, the search for optimal strategies (e.g., exercise and/ or nutritional interventions) to combat this anabolic blunting remains a hot-topic in scientific research.

Leucine, an essential and branched chain amino acid (EAA/BCAA), is thought to be the most potent AA for stimulating muscle protein synthesis (MPS; the muscle building process). Although, as a stand-alone supplement, leucine is unlikely to provoke a robust and prolonged state of MPS, low doses of leucine-enriched mixed-EAAs can elicit similar increases in MPS as compared to a large dose of whey protein. As reduced appetite and increased satiety (feeling fuller) are common with advancing age, supplementation of a low-dose protein (i.e., leucine-enriched) that can adequately stimulate MPS may contribute to muscle health maintenance in older adults and reduce satiation following a meal.

This study aims to examine whether a novel whey protein with greater leucine content ("super-whey") has superior muscle building properties compared to a regular whey protein, at rest and after a single bout of exercise, in both young and older adults

Detailed Description

Not available

Study Timeline

• Study Start: 2021-06-15
• Study First Submitted: 2021-08-04
• Primary Completion: 2022-11-22
• Study Completion: 2022-11-22
• Status Verified: 2023-01
• Study First Submitted QC: 2023-01-17
• Last Update Submitted: 2023-01-17
• Study First Posted: 2023-01-27
• Last Update Posted: 2023-01-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 20

Inclusion Criteria

• Participant is in the desired age-ranges (young adults: 18-35 years; older adults: 65+ years).
• Participant is willing and able to give informed consent for participation in the study.
• Participant is physically able to perform resistance exercise

Exclusion Criteria

• A BMI <18 or >35 kg/m2
• Active cardiovascular, cerebrovascular or respiratory disease: e.g. uncontrolled hypertension (BP > 160/100), angina, heart failure (class III/IV), arrhythmia, right to left cardiac shunt, recent cardiac event, COPD, pulmonary hypertension or recent (6 mo) stroke
• Any metabolic disease
• Clotting dysfunction
• A history of, or current neurological or musculoskeletal conditions (e.g. epilepsy)
• Lactose intolerance
• Having taken part in a research study in the last 3 months involving invasive procedures or an inconvenience allowance

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Isonitrogenous whey protein	Isonitrogenous whey protein	Both protein sources will be given in doses that are considered low/normal, both in relation to recommended dietary advice and commercially available supplements. As such, no adverse reactions or side effects are expected through consumption of these supplementations
Super-Whey protein	Super-Whey protein	Both protein sources will be given in doses that are considered low/normal, both in relation to recommended dietary advice and commercially available supplements. As such, no adverse reactions or side effects are expected through consumption of these supplementations

Primary Outcome Measures

Name	Time	Method
Muscle protein fractional synthetic rate (postprandial)	Assessed at 6 hour mark	Postprandial measures of muscle protein synthesis assessed in muscle tissue (collected by muscle biopsy). This outcome will be assessed following administering a protein drink to obtain muscle protein fractional synthetic rate in the fed state.
Muscle protein fractional synthetic rate (postabsorptive)	Assessed at 3 hour mark	Postabsorptive measures of muscle protein synthesis assessed in muscle tissue (collected by muscle biopsy). This outcome will be assessed prior to administering a protein drink to obtain muscle protein fractional synthetic rate in the fasted state.

Secondary Outcome Measures

Name	Time	Method
Plasma amino acid concentrations	Assessed over 7.5 hours	During the fasted and fed states of the study, blood samples are collected every 20 minutes to capture the plasma amino acid concentrations in the blood at that time-point (24 timepoints assessed). Future analysis using mass-spectroscopy will allow determination of the different amino acid concentrations in the blood plasma collected.

Trial Locations

Locations (1)

Centre of Ageing, Metabolism and Physiology; 🇬🇧 Derby, United Kingdom