Impact of a carbohydrate–electrolyte drink on ingestive behaviour, affect and self-selected intensity during recreational exercise after 24-h fluid restriction

This study examined the effects of a carbohydrate–electrolyte drink on voluntary fluid intake, affect and self-selected intensity during recreational exercise after fluid restriction. In a randomised counterbalanced design, ten physically active adults were dehydrated via a 24-h period of fluid restriction before completing two 20-min bouts of cardiovascular exercise, 20-min of resistance exercise and 20 min on a cycle ergometer at a self-selected intensity with ad libitum access to water (W) or a carbohydrate–electrolyte solution (CES). Fluid restriction induced hypohydration of ∼1.2% initial body mass. Fluid intake during exercise was greater with CES (2105 ± 363 vs. 1470 ± 429 mL; P < 0.01) and resulted in more adequate hydration (−0.03 ± 0.65 vs. −1.26 ± 0.80%; P < 0.01). Plasma glucose concentrations (4.48 ± 0.40 vs. 4.28 ± 0.32 mmol L−1; P < 0.01) and pleasure ratings (2.63 ± 1.17 vs. 1.81 ± 1.37; P < 0.01) were greater with CES than W. Mean power output during exercise performed at a self-selected intensity was 5.6% greater with CES (171 ± 63 vs. 162 ± 60 W; P < 0.05). In physically active adults performing a ‘real-life’ recreational exercise simulation, CES resulted in more adequate hydration and an enhanced affective experience that corresponded with an increase in self-selected exercise intensity.