Objectives: To assess the physiological and performance effects of a 12% carbohydrate-electrolyte beverage consumed at practically applicable time-points (i.e., before each half) throughout simulated soccer match-play. Design: Randomised, counterbalanced, crossover. Methods: Fed players (n = 15) performed 90-min of soccer-specific exercise (including self-paced exercise at the end of each half). Players consumed carbohydrate-electrolyte (CHO; 60 g × 500 ml-1, Na+ 205 mg × 500 ml-1), placebo-electrolyte (PL) or water (Wat) beverages at the end of the warm-up (250 ml) and half-time (250 ml plus ad-libitum water). Blood was drawn before each half and every 15-min during exercise. Physical (15-m sprinting, countermovement jumps, self-paced distance, acceleration/deceleration count), technical (dribbling) and cognitive (memory, attention, decision-making) performance was assessed. Ratings of perceived exertion (RPE) and abdominal discomfort were measured. Results: Against Wat and PL, CHO increased (all p < 0.05) mean accelerations &gt;1.5 m·s-2 during self-paced exercise (&gt;+25%) and dribbling speed from 60-min onwards (&gt;+3%). Mean sprinting speed improved (+2.7%) in CHO versus Wat. Blood glucose increased before and during each half in CHO versus PL and Wat (all p &lt; 0.05). A 27% decline in glycaemia occurred at 60-min in CHO. RPE was comparable between trials. Cognition reduced post-exercise (p < 0.05); this decline was not attenuated by CHO. Abdominal discomfort increased during exercise but was similar between trials. Conclusions: Using more realistic fluid ingestion timings than have been examined previously, consuming a 12% carbohydrate-electrolyte beverage increased blood glucose, self-paced exercise performance, and improved dribbling speed in the final 30-min of exercise compared to water and placebo. Carbohydrates did not attenuate post-exercise reductions in cognition.
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