The Impact of Pre-Exercise Carbohydrate Meal on the Effects of Yerba Mate Drink on Metabolism, Performance, and Antioxidant Status in Trained Male Cyclists

Introduction: The consumption of yerba mate (YM), a source of antioxidants, in a fasted state increases fatty acid oxidation (FAT ox ) during low-moderate-intensity exercise and improves performance in high-intensity exercise. However, the impact of a pre-exercise carbohydrate (CHO) meal on YM effects during exercise is unknown. Objective: We investigated the effects of yerba mate drink (YMD) consumed in the fasted state (YMD-F) or after a CHO meal (YMD-CHO) on measurements of metabolism, performance, and blood oxidative stress markers in cycling exercise. Methods: In a randomized, repeated-measures, crossover design, eight trained male cyclists ingested (i) YMD-CHO, (ii)YMD-F, or (iii) control-water and CHO meal (Control-CHO). The YMD (an infusion of 5 g of ultrarefined leaves in 250 mL of water) was taken for 7 days and 40 min before exercise. CHO meal (1 g/kg body mass) was consumed 60 min before exercise. The cycling protocol included a 40-min low-intensity (similar to 53% (V)over dotO(2)peak ) constant load test (CLT); a 20-min time trial (TT); and 4 x 10-s all-out sprints. Blood samples and respiratory gases were collected before, during, and/or after tests. Results: During CLT, YMD-CHO increased FAT(ox) similar to 13% vs. YMD-F (P = 0.041) and similar to 27% vs. Control-CHO (P < 0.001). During TT, YMD-CHO increased FAT(ox) similar to 160% vs. YMD-F (P < 0.001) and similar to 150% vs. Control-CHO (P < 0.001). Power output during TT improved similar to 3% (P = 0.022) in YMD-CHO vs. Control-CHO and was strongly correlated with changes in serum total antioxidant capacity (r = -0.87) and oxidative stress index (r = 0.76) at post-exercise in YMD-CHO. Performance in sprints was not affected by YMD. Conclusion: CHO intake did not negate the effect of YMD on FAT(ox) or TT performance. Instead, a synergism between the two dietary strategies may be present.