Mouth rinsing a carbohydrate solution improves exercise performance in athletes, but whether it benefits exercise performance in overweight adults is unknown.
PURPOSE: This study determined the effect of carbohydrate mouth rinse on running performance and energy intake in overweight participants.
METHODS: In a counterbalanced and placebo controlled design, 21 males (Age: 21.0 ± 1.8; BMI: 27.6 ± 1.1) with depleted glycogen stores, completed a graded treadmill exercise test to exhaustion following a 10-s mouth rinse with a solution of either 7.5% carbohydrate (CHO), placebo (PLA), or a no rinse (CON), followed by standardized meal. Anthropometrics, 24-hour energy intake, heart rate (HR), oxygen consumption (VO2), and rating of perceived exertion (RPE) were measured.
RESULTS: All participants completed the trials. Mean time to exhaustion in seconds per treatment was greater for CHO (1048.7 ± 91.8) versus PLA (1034.4 ± 83.6, p = 0.02), and CON (1012.2 ± 75.7, p = 0.001) (pη2 = 0.430). Peak treadmill speed (km/h) was greater for CHO (11.5 ± 0.8) versus PLA (11.3 ± 0.7, p = 0.011), and CON (11.2 ± 0.6, p = 0.003) (pη2 = 0.354). Subsequent trial energy intake (Kcal) was lower for CHO (577.5 ± 50.5) versus PLA (622.8 ± 78.3, p < 0.0001), and CON (615.2 ± 69.4, p < 0.0001) (pη2 = 0.530). The 24-hour energy intake, HR, VO2 and RPE did not change (P > 0.05).
CONCLUSION: Carbohydrate mouth rinse improves both running duration and speed in overweight adults with depleted glycogen stores.