Postexercise carbohydrate-protein supplementation improves subsequent exercise performance and intracellular signaling for protein synthesis

J Strength Cond Res. 2011 May;25(5):1210-24. doi: 10.1519/JSC.0b013e318212db21.

Abstract

Postexercise carbohydrate-protein (CHO + PRO) supplementation has been proposed to improve recovery and subsequent endurance performance compared to CHO supplementation. This study compared the effects of a CHO + PRO supplement in the form of chocolate milk (CM), isocaloric CHO, and placebo (PLA) on recovery and subsequent exercise performance. Ten cyclists performed 3 trials, cycling 1.5 hours at 70% VO₂max plus 10 minutes of intervals. They ingested supplements immediately postexercise and 2 hours into a 4-hour recovery. Biopsies were performed at recovery minutes 0, 45, and 240 (R0, R45, REnd). Postrecovery, subjects performed a 40-km time trial (TT). The TT time was faster in CM than in CHO and in PLA (79.43 ± 2.11 vs. 85.74 ± 3.44 and 86.92 ± 3.28 minutes, p ≤ 0.05). Muscle glycogen resynthesis was higher in CM and in CHO than in PLA (23.58 and 30.58 vs. 7.05 μmol·g⁻¹ wet weight, p ≤ 0.05). The mammalian target of rapamycin phosphorylation was greater at R45 in CM than in CHO or in PLA (174.4 ± 36.3 vs. 131.3 ± 28.1 and 73.7 ± 7.8% standard, p ≤ 0.05) and at REnd in CM than in PLA (94.5 ± 9.9 vs. 69.1 ± 3.8%, p ≤ 0.05). rpS6 phosphorylation was greater in CM than in PLA at R45 (41.0 ± 8.3 vs. 15.3 ± 2.9%, p ≤ 0.05) and REnd (16.8 ± 2.8 vs. 8.4 ± 1.9%, p ≤ 0.05). FOXO3A phosphorylation was greater at R45 in CM and in CHO than in PLA (84.7 ± 6.7 and 85.4 ± 4.7 vs. 69.2 ± 5.5%, p ≤ 0.05). These results indicate that postexercise CM supplementation can improve subsequent exercise performance and provide a greater intracellular signaling stimulus for PRO synthesis compared to CHO and placebo.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Biopsy, Needle
  • Blood Chemical Analysis
  • Cross-Over Studies
  • Dietary Carbohydrates / administration & dosage*
  • Dietary Proteins / administration & dosage*
  • Dietary Supplements*
  • Double-Blind Method
  • Exercise / physiology*
  • Exercise Test / methods
  • Female
  • Glycogen / metabolism
  • Humans
  • Male
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / pathology
  • Physical Endurance / drug effects*
  • Physical Endurance / physiology
  • Physical Exertion / physiology
  • Protein Biosynthesis / drug effects*
  • Protein Biosynthesis / physiology
  • Reference Values
  • Signal Transduction / drug effects
  • Young Adult

Substances

  • Dietary Carbohydrates
  • Dietary Proteins
  • Glycogen