Who are we?


Signup for

Online registration

Log in to register
your trial

Search a trial




van CCT (UK)

van CCT (UK)

The effects of protein dose response on myofibrillar and mitochondral protein synthesis after endurance exercise in young men

- candidate number21836
- NTR NumberNTR5111
- ISRCTNISRCTN no longer applicable
- Date ISRCTN created
- date ISRCTN requested
- Date Registered NTR23-mrt-2015
- Secondary IDsNL52519.068.15 METC Maastricht University
- Public TitleThe effects of protein dose response on myofibrillar and mitochondral protein synthesis after endurance exercise in young men
- Scientific TitleThe effects of protein dose response on myofibrillar and mitochondral protein synthesis after endurance exercise in young men
- hypothesis30 grams of dietary protein ingestion is necessary to maximize whole-body, myofibrillar, and mitochondrial muscle protein synthetic response after a single bout of endurance exercise in healthy young males. Lower doses of protein (ie. 0 and 15 g) will be suboptimal while higher doses (ie. 45 g) will not induce a greater protein synthetic response.
- Healt Condition(s) or Problem(s) studiedYoung adults, Muscle protein synthesis
- Inclusion criteria- Males
- Aged between 20-30 years
- Bodyweight between 65-95 kg inclusive
- Healthy, moderately trained
- BMI < 25 kg/m2
- Having given informed consent
- Exclusion criteria- Having any identified metabolic or intestinal disorders
- Use of tobacco products
- Non-steroidal anti-inflammatory drugs (NSAID) in the 4 days prior to the experimental trial
- Allergies to milk proteins (whey or casein)
- Arthritic conditions
- A history of neuromuscular problems
- Previous participation in amino acid tracer studies
- Individuals on any medications known to affect protein metabolism (i.e. corticosteroids, non-steroidal anti-inflammatories, or prescription strength acne medications).
- Diabetes
- Training more than 4 days per week
- VO2max < 35 ml/kg/min or > 70 ml/kg/min
- Phenylketonuria
- lactose intolerance
- blood donation within two months of study initiation
- mec approval receivedno
- multicenter trialno
- randomisedyes
- masking/blindingDouble
- controlPlacebo
- groupParallel
- TypeSingle arm
- Studytypeintervention
- planned startdate 1-apr-2015
- planned closingdate1-apr-2017
- Target number of participants64
- Interventionsexercise bout and protein drink with different doses
- Primary outcomeMuscle protein synthesis rate (myofibrillar and mitochondrial)
- Secondary outcome• The fractional synthetic rate (FSR) of muscle protein synthesis (myofibrillar, and mitochondrial proteins) from 0-3 and 3-6 hours in the post-prandial period.
• Plasma free L-[ring-2H5]-phenylalanine enrichment (expressed as MPE)
• Plasma free L-[ring-2H4]-tyrosine enrichment (expressed as MPE)
• Plasma free L-[3,5-2H2]-tyrosine enrichment (expressed as MPE)
• Plasma free L-[ring-2H5]-phenylalanine enrichment
• Plasma free L-[1-13C]-leucine enrichment
• Plasma free L-[1-13C]-KIC enrichment
• Plasma total phenylalanine (expressed as ́mol/L)
• Plasma total tyrosine (expressed as ́mol/L)
• Total plasma amino acids (AAmax [́mol/L])
• Plasma glucose (glucosemax [mmol/L])
• Plasma insulin (insulinmax [mU/L])
- Timepointst=0 drink t=0, t=3,t=6 muscle biopsies, 14 blood draws
- Trial web site
- statusplanned
- Sponsor/Initiator NUTRIM School for Nutrition, Toxicology, and Metabolism Maastricht University
- Funding
(Source(s) of Monetary or Material Support)
- Publications
- Brief summaryRationale: Dietary protein intake after exercise is necessary to maximally stimulate muscle protein synthesis rates [1]. Previous studies have shown that the ingestion of 20 grams of both egg and whey protein is sufficient to maximize both mixed and myofibrillar muscle protein synthesis after resistance type exercise [2, 3]. In addition, it has been observed that 20 grams of protein intake is sufficient to stimulate myofibrillar muscle protein synthesis, but not mitochondrial muscle protein synthesis, after endurance exercise [4]. It is reasonable to suggest that mitochondrial muscle protein synthesis may be particularly important for endurance athletes, as it will improve the oxidative capacity of the skeletal muscle in this athletic population. It remains to be elucidated whether higher doses (>20 grams) of protein ingestion are necessary to enhance mitochondrial muscle protein synthesis rates after endurance exercise. In addition, the effects of different doses of milk protein, as source of dietary protein, have never been tested on myofibrillar and mitochondrial muscle protein synthesis after endurance exercise. We aim to fill these gaps in our understanding. Objective: To define the dose-response relationship after intrinsically labeled milk protein ingestion on whole-body, myofibrillar, and mitochondrial muscle protein synthesis after a single bout of endurance exercise in young men. Study design: Parallel design, randomized, placebo controlled, double blind.
Study population: 48 young (20-30 y inclusive) healthy males.
Intervention (if applicable): Subjects will perform endurance exercise and consume a combination of carbohydrate (45 gr) and different doses of intrinsically labeled milk protein (0, 15, 30, 45 gr). In addition, continuous intravenous tracer infusions will be applied, with plasma and muscle samples collected.
Main study parameters/endpoints: Primary: myofibrillar, and mitochondrial protein bound [13C6] phenylalanine and [13C6] leucine enrichments. Secondary: plasma glucose, insulin, leucine, phenylalanine, tyrosine, plasma [13C6]phenylalanine, plasma [13C6] leucine, plasma D5-phenylalanine and plasma (3,5-D2)-tyrosine enrichments.
- Main changes (audit trail)
- RECORD23-mrt-2015 - 26-apr-2015

  • Indien u gegevens wilt toevoegen of veranderen, kunt u een mail sturen naar