Casein Ingestion Does Not Increase Muscle Connective Tissue Protein Synthesis Rates

Jorn Trommelen, Andrew M Holwerda, Joan M Senden, Joy P B Goessens, Janneau VAN Kranenburg, Annemie P Gijsen, Lex B Verdijk, Luc J C VAN Loon

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

PURPOSE: This study aimed to assess the effect of dietary protein ingestion on intramuscular connective tissue protein synthesis rates during overnight recovery from a single bout of resistance exercise.

METHODS: Thirty-six healthy, young males were randomly assigned to one of three treatments. One group ingested 30 g intrinsically L-[1-C]-phenylalanine-labeled casein protein before sleep (PRO, n = 12). The other two groups performed a bout of resistance exercise in the evening and ingested either placebo (EX, n = 12) or 30 g intrinsically L-[1-C]-phenylalanine-labeled casein protein before sleep (EX + PRO, n = 12). Continuous intravenous infusions of L-[ring-H5]-phenylalanine and L-[1-C]-leucine were applied, and blood and muscle tissue samples were collected to assess connective tissue protein synthesis rates and dietary protein-derived amino acid incorporation in the connective tissue protein fraction.

RESULTS: Resistance exercise resulted in higher connective tissue protein synthesis rates when compared with rest (0.086 ± 0.017%·h [EX] and 0.080 ± 0.019%·h [EX + PRO] vs 0.059 ± 0.016%·h [PRO]; P < 0.05). Postexercise casein protein ingestion did not result in higher connective tissue protein synthesis rates when compared with postexercise placebo ingestion (P = 1.00). Dietary protein-derived amino acids were incorporated into the connective tissue protein fraction at rest, and to a greater extent during recovery from exercise (P = 0.002).

CONCLUSION: Resistance exercise increases intramuscular connective tissue protein synthesis rates during overnight sleep, with no further effect of postexercise protein ingestion. However, dietary protein-derived amino acids are being used as precursors to support de novo connective tissue protein synthesis.

Original languageEnglish
Pages (from-to)1983-1991
Number of pages9
JournalMedicine & Science in Sports & Exercise
Volume52
Issue number9
DOIs
Publication statusPublished - 1 Sep 2020

Fingerprint Dive into the research topics of 'Casein Ingestion Does Not Increase Muscle Connective Tissue Protein Synthesis Rates'. Together they form a unique fingerprint.

Cite this