Despite the intensity of RSE being higher than ISE [3], CHO ingestion affects the metabolic response to team sport exercise, with a significant increase in glucose concentration found throughout exercise [5, 51]. The mechanisms driving this increased blood glucose concentration are largely unknown. Blood glucose concentration initially increases after ingesting CAF + CHO or PLA + CHO and it may be suppressed by endogenous glucose production [52]. The blood glucose levels gradually decreased in the PLA + CHO trial during the RSE, suggesting that intense sprint exercise increases fuel requirements in working muscles and obligates more blood glucose to muscle cells during the RSE.

By contrast, the CAF + CHO exhibited higher blood glucose levels during the RSE, partly because caffeine is crucial for maintaining blood glucose concentration by enhancing glycolytic turnover [11]. Although Z-VAD-FMK the exact mechanisms of carbohydrate ingestion on exercise

performance, especially for exercise duration less than 1 hour, are not well understood, two major explanations are commonly used to interpret the possible ergogenic effects of carbohydrate. Firstly, the general metabolic response to prolonged intermittent exercise with CHO administration is an increase in plasma glucose concentration and higher rates of glucose oxidation during the later exercise stage [9]. Secondly, the presence of carbohydrate in the mouth Ixazomib mw has been shown to stimulate the receptors in the oral cavity, thus activating specific areas

of the brain associated with reward and the regulation of motor activity [27]. CHO ingestion may increase blood glucose concentrations, however, it should be noted that the improved performance in previous studies [45] might be attributed to the glycogen-depleted state prior to the intermittent sprint exercise. In this study, we asked participants to consume a standardized meal 2 hours before exercise test to mimic the real-life situation, e.g., fed athletes before competition, in each trial. The results indicate that ingestion of PLA + CHO provided a small but significant benefit on RSE performance in female athletes. Nevertheless, Colombani et al. [53] reported that CHO administration might PLEK2 not induce performance improvements in male athletes during exercise lasting less than 70-min in postprandial state. The increases in blood glucose levels and repeated sprint performance induced by CHO ingestion may also involve the central governor. Gastric empty rate of a CHO drink could be slowed by the hypertonic drink [54] and high-intensity intermittent sprint [55]. Jeukendrup et al. [56] reported that CHO ingestion has no effects on exogenous glucose uptake and total CHO oxidation during short-term (~1 hour) high-intensity cycling exercise.