title: Carbohydrate mouth rinsing in the fed state: lack of enhancement of time-trial performance.
abstract: It has been reported previously that mouth rinsing with a carbohydrate-containing solution can improve cycling performance. The purpose of the current study was to investigate the impact of such a carbohydrate mouth rinse on exercise performance during a simulated time trial in a more practical, postprandial setting. Fourteen male endurance-trained athletes were selected to perform 2 exercise tests in the morning after consuming a standardized breakfast. They performed an approximately 1-hr time trial on a cycle ergometer while rinsing their mouths with either a 6.4% maltodextrin solution (CHO) or water (PLA) after every 12.5% of the set amount of work. Borg's rating of perceived exertion (RPE) was assessed after every 25% of the set amount of work, and power output and heart rate were recorded continuously throughout the test. Performance time did not differ between treatments and averaged 68.14 +/- 1.14 and 67.52 +/- 1.00 min in CHO and PLA, respectively (p = .57). In accordance, average power output (265 +/- 5 vs. 266 +/- 5 W,p = .58), heart rate (169 +/- 2 vs. 168 +/- 2 beats/min, p = .43), and RPE (16.4 +/- 0.3 vs. 16.7 +/- 0.3 W, p = .26) did not differ between treatments. Furthermore, after dividing the trial into 8 s, no differences in power output, heart rate, or perceived exertion were observed over time between treatments. Carbohydrate mouth rinsing does not improve time-trial performance when exercise is performed in a practical, postprandial setting.
authors.affiliation: Nutrition and Toxicology Research Institute, Maastricht, Maastricht University, The Netherlands.
authors.forename: Milou
authors.initials: M
authors.lastname: Beelen
authors.forename: Jort
authors.initials: J
authors.lastname: Berghuis
authors.forename: Ben
authors.initials: B
authors.lastname: Bonaparte
authors.forename: Sam B
authors.initials: SB
authors.lastname: Ballak
authors.forename: Asker E
authors.initials: AE
authors.lastname: Jeukendrup
authors.forename: Luc J C
authors.initials: LJ
authors.lastname: van Loon
mesh_terms: D054874:Athletic Performance / Q000502:physiology*; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000494:pharmacology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D009067:Mouthwashes; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D005082:Physical Exertion / Q000187:drug effects / Q000502:physiology; D011134:Polysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D019518:Postprandial Period; D013997:Time Factors; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates; D009067:Mouthwashes; D011134:Polysaccharides; C008315:maltodextrin