Cited by 104Muscle metabolism and nutritionNutrition and Health in AgingMuscle Physiology and Disorders

Co-ingestion of leucine with protein does not further augment post-exercise muscle protein synthesis rates in elderly men

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Koopman, René, Verdijk, Lex B., Beelen, Milou, Gorselink, Marchel, Kruseman, Arie Nieuwenhuijzen, Wagenmakers, Anton J. M., Kuipers, Harm, van Loon, Luc J.C.·2008·British Journal Of Nutrition

Abstract

Leucine has been suggested to have the potential to modulate muscle protein metabolism by increasing muscle protein synthesis. The objective of this study was to investigate the surplus value of the co-ingestion of free leucine with protein hydrolysate and carbohydrate following physical activity in elderly men. Eight elderly men (mean age 73 +/- 1 years) were randomly assigned to two cross-over treatments consuming either carbohydrate and protein hydrolysate (CHO+PRO) or carbohydrate, protein hydrolysate with additional leucine (CHO+PRO+leu) after performing 30 min of standardized physical activity. Primed, continuous infusions with L-[ring-(13)C(6)]phenylalanine and L-[ring-(2)H(2)]tyrosine were applied, and blood and muscle samples were collected to assess whole-body protein turnover as well as protein fractional synthetic rate in the vastus lateralis muscle over a 6 h period. Whole-body protein breakdown and synthesis rates were not different between treatments. Phenylalanine oxidation rates were significantly lower in the CHO+PRO+leu v. CHO+PRO treatment. As a result, whole-body protein balance was significantly greater in the CHO+PRO+leu compared to the CHO+PRO treatment (23.8 (SEM 0.3) v. 23.2 (SEM 0.3) micromol/kg per h, respectively; P < 0.05). Mixed muscle fractional synthetic rate averaged 0.081 (SEM 0.003) and 0.082 (SEM 0.006) %/h in the CHO+PRO+leu and CHO+PRO treatment, respectively (NS). Co-ingestion of leucine with carbohydrate and protein following physical activity does not further elevate muscle protein fractional synthetic rate in elderly men when ample protein is ingested.

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  • Leucine fortification has been shown, though not always, to augment the MPS response to suboptimal doses of animal protein.

    “In line, leucine fortification has been shown [70,97,98], though not always [99], to augment the MPS response to suboptimal doses of animal protein.”

    From Nutritional Considerations for the Vegan Athlete (2023) · cites this paper as [99]

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Authors
Koopman, R., Verdijk, L. B., Beelen, M., Gorselink, M., Kruseman, A. N., Wagenmakers, A. J. M., Kuipers, H., & van Loon, L. J. C.
Affiliations
  • Maastricht University (NL)
  • University of Birmingham (GB)
Corresponding author
Koopman, René
Venue
British Journal Of Nutrition
Published
2008-03
Volume
99
Issue
3
Pages
571-580
ISSN
  • 0007-1145 (ISSN-L)
  • 1475-2662
OpenAlex
W2020049342
Cited by
104
References
47
Citations by year
2026: 1 · 2025: 2 · 2024: 1 · 2023: 2 · 2022: 5 · 2021: 1 · 2020: 2 · 2019: 3 · 2018: 3 · 2017: 4 · 2016: 11 · 2015: 5 · 2014: 10 · 2013: 6 · 2012: 11
FWCI
3.73
Type
journal article
Language
en
Open access
Locations
  • British Journal Of Nutrition (publishedVersion)
  • PubMed (publishedVersion)
  • Research Publications (Maastricht University) (publishedVersion, other-oa)
  • University of Birmingham Research Portal (University of Birmingham) (submittedVersion, other-oa)
  • Research Publications (Maastricht University) (submittedVersion, other-oa)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
  • Health Sciences › Medicine › Physiology › Nutrition and Health in Aging
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Muscle Physiology and Disorders
Keywords
leucine supplementation, muscle protein synthesis, older men, protein hydrolysates, carbohydrate intake, phenylalanine oxidation, vastus lateralis, protein turnover, aging
MeSH terms
Whey Proteins, Aged, Aging, Amino Acids, Blood Glucose, Diet, Dietary Carbohydrates, Dietary Proteins, Humans, Insulin, Leucine, Male, Milk Proteins, Muscle Proteins, Proteins, Exercise, Muscle, Skeletal, Cross-Over Studies, Dietary Supplements

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