Variable duration of decaffeinated green tea extract ingestion on exercise metabolism

source extracted confidence: high 2026-04-09
#adipose-tissue #adult #camellia-sinensis #carbohydrate-metabolism #catechin

Variable duration of decaffeinated green tea extract ingestion on exercise metabolism

Randell et al., 2014 | Med Sci Sports Exerc | Rct

Citation

Randell Rebecca K, Hodgson Adrian B, ... Jeukendrup Asker E. Variable duration of decaffeinated green tea extract ingestion on exercise metabolism. Med Sci Sports Exerc. 2014-Jun;46(6):1185-93. doi:10.1249/MSS.0000000000000205

Abstract

PURPOSE: The aim of this study was to investigate if the duration of decaffeinated green tea extract (dGTE) ingestion plays a role in augmenting fat oxidation rates during moderate-intensity exercise. METHODS: In a crossover, placebo-controlled design, 19 healthy males (mean ± SD; age = 21 ± 2 yr, weight = 75.0 ± 7.0 kg, body mass index = 23.2 ± 2.2 kg·m, maximal oxygen consumption [V˙O2max] = 55.4 ± 4.6 mL·kg·min) ingested dGTE and placebo (PLA) for 28 d, separated by a 28-d washout period. On the first day (dGTE 1 or PLA 1) and after 7 d (dGTE 7 or PLA 7) and 28 d (dGTE 28 or PLA 28), participants completed a 30-min cycle exercise bout (50% Wmax), 2 h after ingestion. Indirect calorimetry was used to calculate rates of whole-body fat and carbohydrate oxidation during exercise. Blood samples were collected at rest and during exercise for analysis of plasma fatty acids, glycerol, and epigallocatechin gallate. RESULTS: The ingestion of dGTE did not significantly change whole-body fat oxidation rates during exercise on day 1, 7, or 28 compared with PLA. There were also no changes in plasma concentrations of fatty acids and glycerol at rest and during exercise as a result of dGTE ingestion at any time point compared with PLA. Plasma epigallocatechin gallate concentrations, immediately before the exercise bout, in the three dGTE trials were elevated compared with PLA but not different between 1, 7, and 28 d. CONCLUSION: In contrast to previous reports, we found that the duration of dGTE ingestion had no effect on whole-body fat oxidation rates or fat metabolism-related blood metabolites during exercise in physically active healthy males.

Key Findings

The ingestion of dGTE did not significantly change whole-body fat oxidation rates during exercise on day 1, 7, or 28 compared with PLA. There were also no changes in plasma concentrations of fatty acids and glycerol at rest and during exercise as a result of dGTE ingestion at any time point compared with PLA. Plasma epigallocatechin gallate concentrations, immediately before the exercise bout, in the three dGTE trials were elevated compared with PLA but not different between 1, 7, and 28 d.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size See abstract
Age Range See abstract
Condition See abstract

MeSH Terms

  • Adipose Tissue
  • Adult
  • Camellia sinensis
  • Carbohydrate Metabolism
  • Catechin
  • Cross-Over Studies
  • Energy Metabolism
  • Exercise
  • Fatty Acids
  • Glycerol
  • Humans
  • Male
  • Oxidation-Reduction
  • Plant Extracts
  • Tea

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't
  • Vertical: green-tea

Provenance

Source extracted via PubMed E-utilities API on 2026-04-10