Glucose Mouth Rinse And Mouth Spray Enhance Prolonged Exercise Performance In Healthy Male College Students

Abstract

PURPOSE: Research supports the ergogenic effects of glucose mouth rinse (GMR) during prolonged performance, however, the effects of glucose mouth spray (GMS) is limited. The aim of this study was to investigate the effects of GMR and GMS on prolonged exercise. METHODS: Nine male college students (age, 22.2 ± 1.1 years; height, 172.0 ± 4.7 cm; body weight, 66.4 ± 6.1 kg; VO2peak, 3014.9 ± 251.6 ml/min) performed constant load exercise using an electromagnetic brake-type bicycle ergometer (PowerMax VIII; Combi Wellness, Japan). The participants performed constant load exercise for 60 min (intensity 40% VO2max) and then, four sets of the Wingate test (three 30-s Wingate tests with 4 min recovery period between each test) while they were performing constant load exercise for 30 min (intensity 40% VO2max). Each trial lasts for 4.8 hrs. All participants completed a total of four experimental trials: (1) ingesting glucose (G) solution (500 ml) at the beginning, (2) 15 GMR, (3) 15 GMS - 5 times rinse or spray during each 30 min constant load, and (4) water (control) ad libitum during the entire trial. The exercise max power value, blood glucose levels, and rating of perceived exertion, were measured. Repeated two-way analysis of variance (ANOVA) was used for comparison of the data among G, GMR, GMS and water. RESULTS: The % value of the average max power at the 3rd and 4th sets for each trial (G, GMR, and GMS) were significantly higher compared to the control (water): 3rd set; 95.0 ± 1.5%, 96.9 ± 1.5%, 96.5 ± 1.4%, and 90.2 ± 1.5% (control), p < 0.01, respectively, and 4th set; 89.8 ± 1.5%, 92.8 ± 1.5%, 92.9 ± 1.5%, and 85.1 ± 1.5% (control), p < 0.01, respectively. Blood glucose level at the 3rd and 4th sets of G, GMR, GMS were significantly higher compared to the control: 3rd set; 80.7 ± 4.5mg/dl, 81.4 ± 2.5 mg/dl, and 78.3 ± 2.9 mg/dl, 71.3 ± 3.7 mg/dl (control), p < 0.05, respectively, and 4th set; 81.8 ± 5.9mg/dl, 81.4 ± 2.5mg/dl, 78.3 ± 2.9ml/dl, and 71.0 ± 2.8 mg/d (control), p < 0.01, respectively. During the 3rd and 4th sets, all G, GMR and GMS showed significantly lower rating of perceived exertion compared to water (control), p < 0.05. CONCLUSION: GMR and GMS resulted in improved endurance performance. The role of G receptors in the mouth during prolonged exercise warrants further investigation.