CClinicalTrials.gg
RecruitingNCT06971822Updated Apr 28, 2026

Assessing the Impact of a Leucine Enriched Whey Protein vs Isonitrogenous Whey on Muscle Protein Synthetic Responses in the Rested and Acute Post Exercise States in Older Adults

An interventional study of Protein Supplementation in Healthy Male Volunteers Over 65, sponsored by University of Nottingham. Recruiting at 1 site in United Kingdom. Open to male participants aged 65 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-28.

Sponsored by University of Nottingham · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Started Mar 2025; still recruiting 1 year 6 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
30
Allocation
Randomized
Ages
65 Years and older
Sex
Male
01

Study summary

Occupying \~45-55% of body mass, skeletal muscle is the largest organ of the body and plays a pivotal role in locomotion, structural support and whole-body metabolic health. Additionally, skeletal muscle serves as the largest reservoir of amino acids (AA), which negatively adapts in states of disease and fasting to provide energy and AAs for vital organs, but also positively adapts to nutrition (i.e. protein consumption) and exercise (i.e. resistance exercise (RE)). With the current global ageing population, pressure on health and social care systems is continuing to mount due to increased frailty and other age-related co-morbidities. Sarcopenia, the loss of muscle mass (atrophy) and function with advancing age, predisposes an individual to an increased likelihood of physical disability, falls/fractures and mortality. Whilst sarcopenia is multifaceted and has no sole cause, reduced responses to environmental stimuli (namely nutrition (i.e. protein feeding) and exercise) termed "anabolic resistance", appears to be a governing role in the progression of age-related muscle atrophy. The maintenance of muscle mass is regulated by the dynamic relationship between muscle protein synthesis (MPS) and muscle protein breakdown (MPB) with anabolic resistance, therefore, centering upon the blunting of increases in MPS and/or suppression of MPB.

Aged muscle has consistently shown depressed MPS rates following feeding and also exercise when compared to young muscle. Additionally, older individuals need to consume a greater amount of protein compared to younger individuals to drive an MPS increase above baseline levels. This can often prove difficult due to older adults exhibiting increased satiety, likely contributing to the inadequate daily consumption of protein in such populations. Fortifying protein with leucine may, therefore, provide a nutraceutical avenue for combating anabolic resistance in ageing muscle. Leucine, both an essential amino acid (EAA) and branched chain amino acid (BCAA), is the key AA for stimulating MPS via activation of mechanistic target of rapamycin complex 1 (mTORC1), meaning protein rich in leucine may be advantageous to trigger MPS. Recent work has shown that a submaximal protein (10 g) drink enriched with leucine (4.5 g), compared to the non-essential amino acid (NEAA)- alanine (4.5 g), elevated MPS in older individuals, with anabolic signalling also being robustly triggered when administering \~6g BCAAs contain \~2.6 g leucine in older adults. However, research has also shown that in the absence of a full AA profile, leucine alone failed to stimulate MPS in postmenopausal women. It, therefore, remains inconclusive whether standalone or adjuvant supplementation of leucine is most effective to sufficiently stimulate MPS across aged populations and it remains to be investigated whether submaximal doses of complete protein enriched with leucine may lead to enhanced muscle anabolism in older adults.

In this study, we aim to assess the impact of dietary supplementation with a "super-whey" (SW) protein (with \~40% enhanced leucine and \~20% enhanced EAAs) vs. isonitrogenous whey protein (WP) on muscle protein synthesis (MPS). We will examine these effects both in the rested state, as well as the 24 hour post-exercise period under tightly controlled activity and feeding conditions.

02

Conditions studied

  • Healthy Male Volunteers Over 65

Browse trials for

Keywords

  • Leucine
  • Muscle Mass
  • Sarcopenia
  • Nutrition
  • Protein
03

In context

Sarcopenia

1,208 studies on the registry are indexed under Sarcopenia; 402 are open to participants now.

This study's planned enrollment of 30 is below the median of 60 across 775 interventional studies indexed under Sarcopenia.

Browse Sarcopenia studies →

Lead sponsor

University of Nottingham is the lead sponsor of 455 studies on the registry; 77 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
65 Years and older
Sexes eligible
Male
Accepts healthy volunteers
Yes

Eligibility criteria

Inclusion Criteria:

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
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
30 participants (estimated)

Study arms

  • Active comparator
    Isonitrogenous Whey Protein Group

    This group will receive a 20g supplement of isonitrogenous whey protein supplement with each of their controlled meals on the study visits.

    Dietary Supplement: Protein Supplementation

  • Experimental
    BLG

    This group will receive a 20g supplement of BLG (leucine enriched protein) supplement with each of their controlled meals on the study visits.

    Dietary Supplement: Protein Supplementation

Interventions

  • Dietary supplementProtein Supplementation

    We are assessing the supplementation of a controlled diet with beta-lactoglobulin protein compared to regular isonitrogenous whey protein. We will make these comparisons over both the 24 hour rested and 24 hour post-exercise states. Beta-lactoglobulin has a higher leucine content than traditional whey protein, with this leucine amino acid thought to have a critical role as an anabolic stimulus to initiate muscle protein synthesis.

06

What researchers measure

Primary outcomes

  1. Muscle Protein Synthesis

    We measure myofibrillar fractional synthesis rates (FSR) based on the incorporation of deuterated hydrogen from heavy water (D2O) in the muscle. Participants will consume the heavy water the day before the onset of the study, and then muscle biopsies will be taken at various points over the next three days for rested and post-exercise muscle protein synthesis measures.

    Time frame: From enrollment there is a three day lead in to the study with a controlled diet and limited physical activity, followed by two and a half days of study visits.

07

Study locations

1 of 1 sites recruiting
  • Royal Derby Hospital Medical School
    Derby, Derbyshire DE22 3NE, United Kingdom
    Recruiting
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 28, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06971822
Lead sponsor
University of Nottingham
Responsible party
Philip Atherton (Professor Philip Atherton, University of Nottingham) — Principal investigator
First posted
May 14, 2025
Start date
Mar 14, 2025
Primary completion
Feb 1, 2029 (estimated)
Completion
Feb 28, 2029 (estimated)
Last update
Apr 28, 2026

Study contacts

Jake Cox
Contact
mbyjc16@nottingham.ac.uk
07731 755075
Philip J Atherton
principal investigator · University of Nottingham

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion