Muscle glycogen utilization during exercise following ingestion of alcohol

Harry Smith, Aaron Hengist, Drusus Johnson-Bonson, Jean-Philippe Walhin, Robbie Jones, Kostas Tsintzas, Gregg Afman, Javier Gonzalez, James Betts

Research output: Contribution to journalArticle

Abstract

PURPOSE: Ingested ethanol (EtOH) is metabolized gastrically and hepatically, which may influence resting and exercise metabolism. Previous exercise studies have provided EtOH via intravenous infusion rather than oral ingestion, which alters the metabolic effects of EtOH. No studies to date have investigated the effects of EtOH ingestion on systemic and peripheral (e.g. skeletal muscle) exercise metabolism.
METHODS: Eight men (Mean ± SD, Age: 24 ± 5 y; Body Mass: 76.7 ± 5.6 kg; Height: 1.80 ± 0.04 m; V̇O2peak: 4.1 ± 0.2 L.min-1) performed two bouts of fasted cycling exercise at 55% V̇O2peak for 2-h, with (EtOH) and without (Control) prior ingestion of EtOH 1-h and immediately before exercise (total dose: 0.1 g∙kg lean body mass-1∙h-1; 30.2 ± 1.1 g 40% ABV Vodka; fed in 2 equal boluses) in a randomized order, separated by 7-10 days.
RESULTS: Muscle glycogen breakdown during exercise was not different between conditions (Control: -257.7 [-330.8, 184.6] vs EtOH: -221.4 [-287.6, 141.4] mmol∙kg dm-1; means with normalized 95% confident intervals). Mean plasma glucose concentrations during exercise were similar (Control: 5.26 [5.17, 5.34] vs EtOH: 5.26 [5.18, 5.34] mmol∙L-1; p = 0.04). EtOH ingestion resulted in similar plasma non-esterified fatty acid (NEFA) concentrations compared to rest (Control: 0.43 [0.31,0.55] vs EtOH: 0.30 [0.21,0.40] mmol∙L-1) and during exercise. Mean plasma lactate concentration was higher during the first 30-min of rest following EtOH consumption (mean concentration: Control: 0.83 [0.77, 0.90] vs EtOH 1.00 [0.93, 1.07] mmol∙L-1) but the response during exercise was similar between conditions.
CONCLUSIONS: Ingesting a small dose of EtOH transiently altered resting concentrations of systemic lactate, but not during exercise. Muscle glycogen utilization was similar during exercise with or without prior alcohol ingestion, reflected in similar total whole-body carbohydrate oxidation rates observed.
Original languageEnglish
JournalMedicine & Science in Sports & Exercise
Publication statusAcceptance date - 26 Jun 2020

Cite this