Effect of A Vegetable-based Sports Drink on Hydration During Endurance Exercise

Palatability of sport drinks can encourage increased drinking behavior throughout prolonged exercise bouts and mitigate voluntary dehydration. PURPOSE: The purpose of this study was to assess voluntary drinking behaviors, taste preferences, and fluid balance during endurance exercise performed in a hot environment and compare between a novel vegetable-based beverage (VB), commercial coconut water (CW), and sweet placebo (PLA). METHODS: The study was a double-blind randomized trial with repeated measures for 10 college aged male cyclists. Each subject participated in three, 90 minute cycling sessions after an overnight fast, with 1 week between trials. During each session, the subject drank one of the test beverages ad libitum. Each exercise session was conducted in a thermostatically controlled heat chamber maintained at 30C and 50% humidity. Volume ingested and time of drinking were recorded out of sight of the participants who were not told their drinking behaviors were being monitored. Body fluid balance was assessed as total fluid intake minus fluid output (sweat and urine). After each exercise session, subjects were given a survey to rate palatability characteristics using a 9 cm visual analog scale. RESULTS: Fluid intake was greatest with VB, followed by PLA then CW (888 ± 91 mL, 828 ± 123 mL, 812 ± 114 mL, respectively) (p =0.04, quadratic effect, p = 0.06 linear effect). Net fluid balance at the end of exercise was not different between drinks (CW: -1575 ± 171 mL, PL: -1449 ± 176 mL, SP: -1314 ± 145 mL) (p = 0.08). Survey data indicated significant treatment effects (p < 0.05) for “overall taste”, “flavor rating”, “thirst” at end of exercise, “refreshing”, and “overall satisfaction with the beverage”. CONCLUSION: In conclusion, preference for VB corresponded with increased drinking volume throughout the exercise bout. The increased fluid intake may reduce magnitude of negative fluid balance during exercise in a hot environment.