Adherence
Rinsing the mouth with a 10% carbohydrate (maltodextrin) solution and expectorating it improves cycling time-trial power output in both fed and fasted states, with a greater magnitude of improvement observed in the fasted state.
If you are competing in an event under 90 minutes, rinse your mouth with a sports drink (containing carbs) for 10 seconds every 7-8 minutes during the race, then spit it out. This will likely improve your power output by roughly 2-3%, especially if you haven't eaten a large meal beforehand. It works by signaling your brain, not by providing fuel.
The CHO mouth rinse improved mean power to a greater extent after an overnight fast (282 vs. 273 W, 3.4%; p < 0.01) compared with a fed state (286 vs. 281 W, 1.8%; p < 0.05).
Why this rating
Double-blind, randomized, controlled crossover design with competitive athletes, though sample size is small (n=12).
Source
Effect of a carbohydrate mouth rinse on simulated cycling time-trial performance commenced in a fed or fasted state
Stephen C. Lane et al. · Applied Physiology Nutrition and Metabolism · 2012
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