Short-term green tea extract supplementation attenuates the postprandial blood glucose and insulin response following exercise in overweight men

Green tea extract (GTE) ingestion improves glucose homeostasis in healthy and diabetic humans, but the interactive effect of GTE and exercise is unknown. The present study examined the effect of short-term GTE supplementation on the glycemic response to an oral glucose load at rest and following an acute bout of exercise, as well as substrate oxidation during exercise. Eleven sedentary, overweight men with fasting plasma glucose (FPG) ≥5.6 mmol/L (34±13 y; BMI=32±5 kg•m-2; FPG=6.8±1.0; mean±SD) ingested GTE (3x•d-1, 1050 mg•d-1 total) or placebo (PLA) for 7-d in a double-blind, crossover design. The effects of a 75g glucose drink were assessed on 4 occasions during both GTE and PLA treatments: On days 1 and 5 at rest, and again following an acute bout of exercise on days 3 and 8. The glycemic response was assessed via an indwelling continuous glucose monitor (CGM) and venous blood draws. At rest, 1-h CGM glucose AUC was not different (P>0.05), but the post-exercise response was lower after GTE vs. PLA (330±53 and 393±65 mmol•L-1•min-1, main effect of treatment, PThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author