Epigallocatechin-3-gallate Increases Maximal Oxygen Uptake in Adult Humans

RICHARDS, JENNIFER C.; LONAC, MARK C.; JOHNSON, TYLER K.; SCHWEDER, MELANI M.; BELL, CHRISTOPHER

Medicine & Science in Sports & Exercise: April 2010 - Volume 42 - Issue 4 - pp 739-744
doi: 10.1249/MSS.0b013e3181bcab6c
Basic Sciences

Epigallocatechin-3-gallate (EGCG), a component of green tea, increases endurance performance in animals and promotes fat oxidation during cycle ergometer exercise in adult humans.

Purpose: We have investigated the hypothesis that short-term consumption of EGCG delays the onset of the ventilatory threshold (VT) and increases maximal oxygen uptake (V˙O2max).

Methods: In this randomized, repeated-measures, double-blind study, 19 healthy adults (11 males and 8 females, age = 26 ± 2 yr (mean ± SE)) received seven placebo or seven EGCG (135-mg) pills. Forty-eight hours before data collection, participants began consuming three pills per day; the last pill was taken 2 h before exercise testing. VT and V˙O2max were determined from breath-by-breath indirect calorimetry data collected during continuous incremental stationary cycle ergometer exercise (20-35 W·min−1), from rest until volitional fatigue. Each condition/exercise test was separated by a minimum of 14 d.

Results: Compared with placebo, short-term EGCG consumption increased V˙O2max (3.123 ± 0.187 vs 3.259 ± 0.196 L·min−1, P = 0.04). Maximal work rate (301 ± 15 vs 301 ± 16 W, P = 0.98), maximal RER (1.21 ± 0.01 vs 1.22 ± 0.02, P = 0.27), and maximal HR were unaffected (180 ± 3 vs 180 ± 3 beats·min−1, P = 0.87). In a subset of subjects (n = 11), maximal cardiac output (determined via open-circuit acetylene breathing) was also unaffected by EGCG (29.6 ± 2.2 vs 30.2 ± 1.4 L·min−1, P = 0.70). Contrary to our hypothesis, EGCG decreased V˙O2 at VT (1.57 ± 0.11 vs 1.48 ± 0.10 L·min−1), but this change was not significant (P = 0.06).

Conclusions: Short-term consumption of EGCG increased V˙O2max without affecting maximal cardiac output, suggesting that EGCG may increase arterial-venous oxygen difference.

Department of Health and Exercise Science, Colorado State University, Fort Collins, CO

Address for correspondence: Christopher Bell, Ph.D., Department of Health and Exercise Science, 205E Moby B Complex, Colorado State University, Fort Collins, CO 80523-1582; E-mail: cbell@cahs.colostate.edu.

Submitted for publication June 2009.

Accepted for publication August 2009.

©2010The American College of Sports Medicine