The effect of two different doses of green tea on substrate metabolism and energy expenditure before, during and after one session of aerobic exercise in overweight and obese women

  The purpose of this study was to investigate the effect of two different doses of green tea on substrate metabolism and energy expenditure before, during and after an aerobic exercise session in overweight and obese women. Ten overweight and obese women (weight 80.71 ±11.96 kg) voluntarily participated in a cross-over design. These participants consumed a dose of 500 mg of green tea, a dose of 1000 mg of green tea and placebo with a wash-out period of 12 to 14 days between these three periods. The exercise protocol included running at 75% of the maximum heart rate on treadmill for 30 minutes. The respiratory gases of the participants were collected using a gas analyzer for 30 minutes before exercise in supine position (baseline), 30 minutes during exercise and 30 minutes after exercise (EPOC) to measure carbohydrate oxidation, fat, and energy expenditure. Data were analyzed using MANOVA and ANOVA with repeated measurements tests (α=0.05). The results showed that 500 and 1000 mg of green tea consumptions increased significantly fat oxidation during and after exercise compared with the placebo group. There was no significant difference between the two doses in the above variable. There was no significant difference in carbohydrate oxidation and energy expenditure between the three groups in baseline state, during and after exercise. Overweight and obese women can reduce their body fat using a 500 mg green tea supplement along with doing moderate aerobic exercise