The combined effect of green tea and acute interval sprinting exercise on fat oxidation of trained and untrained males.

Daniel E Gahreman,Yati N Boutcher,Stephen H Boutcher,Sonia Bustamante

doi:10.20463/jenb.2016.03.20.1.1

Daniel E Gahreman, Yati N Boutcher + Show 2 more

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https://doi.org/10.20463/jenb.2016.03.20.1.1

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Abstract

[Purpose]This study investigated the combined effect of green tea and acute interval sprinting exercise on fat oxidation of trained and untrained males.[Methods]Fourteen trained and 14 untrained males ingested one capsule containing either green tea or cellulose with breakfast, lunch, and dinner, 24 hours before two exercise sessions. A fourth capsule was consumed 90 minutes before exercise after overnight NPO (nil per os). Participants performed a 20-minute interval sprinting cycling protocol, consisting of repeated bouts of 8-seconds of sprint cycling (at 65% of maximum power output) and 12-seconds of recovery (at 25% of maximum power output), followed by 75 minutes of post-exercise recovery.[Results]Fat oxidation was significantly greater in the resting condition after green tea ingestion (p < 0.05) compared with the placebo. Fat oxidation was also significantly increased post-exercise in the green tea, compared with the placebo condition (p < 0.01). During and after exercise the plasma glycerol levels significantly increased in both groups after green tea consumption and were significantly higher in the untrained group compared with the trained group (p < 0.05). Compared with the placebo, the plasma epinephrine levels were significantly higher for both groups in the green tea condition during and after exercise, however, norepinephrine levels were only significantly greater, p < 0.05, during and after exercise in the untrained group.[Conclusion]Green tea significantly increased resting and post-exercise fat oxidation and also elevated plasma glycerol and epinephrine levels during and after interval sprinting. Glycerol and norepinephrine levels during interval sprinting were significantly higher in the untrained group compared with the trained group.

Highlights

Overweight and obesity are associated with increased incidence of cardiovascular and metabolic disease[1]
A mechanism underlying the green tea (GT) and fat oxidation effect has not been determined it has been suggested that the catechins in GT inhibit catechol-O methyltransferase, an enzyme that degrades norepinephrine, which results in prolonging the action of sympathetically released norepinephrine[9]
This study examined the effect of GT and interval sprinting exercise (ISE) on fat oxidation of untrained females, whether this response is present in aerobically trained and untrained males is undetermined

Summary

Introduction

Overweight and obesity are associated with increased incidence of cardiovascular and metabolic disease[1]. Treatments used to reduce body fat have included aerobic exercise, appetite suppressants, dieting, and lipase inhibitors[2]. The lack of success of these treatments has raised interest in other fat loss strategies, such as interval sprinting exercise (ISE)[3] and green tea (GT) ingestion[4]. EGCG, which is the most pharmacologically active catechin[6], has been shown to increase fat oxidation, during the postprandial period, as indicated by a reduced respiratory quotient (RQ) during indirect calorimetry[7,8]. A mechanism underlying the GT and fat oxidation effect has not been determined it has been suggested that the catechins in GT inhibit catechol-O methyltransferase, an enzyme that degrades norepinephrine, which results in prolonging the action of sympathetically released norepinephrine[9]

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Conclusion