Mouth rinsing and ingesting a bitter solution improves sprint cycling performance

Area of Science:

• Exercise Physiology
• Sports Science
• Human Performance

Background:

• Carbohydrate (CHO) mouth rinsing is known to enhance endurance, muscle force, and sprint performance.
• The effect of non-CHO tastants on exercise performance remains largely unexplored.

Purpose of the Study:

• To investigate if mouth rinsing and ingesting a bitter quinine solution improves maximal sprint cycling performance.
• To determine the impact of non-carbohydrate tastants on short-duration, high-intensity exercise.

Main Methods:

• Fourteen competitive male cyclists performed a 30-s maximal cycling sprint.
• Participants rinsed their mouths and ingested either a quinine solution, plain water, aspartame solution, or nothing (control).
• Power output, heart rate, perceived exertion, blood lactate, and blood glucose were measured.

Main Results:

• Quinine significantly improved mean power output by 2.4%-3.9% compared to other conditions.
• Peak power output was significantly higher with quinine versus water and control conditions.
• No significant differences in performance or physiological variables were observed between water, aspartame, and control conditions.

Conclusions:

• Mouth rinsing and ingesting a bitter-tasting quinine solution can enhance maximal sprint cycling performance.
• This study provides novel evidence for the ergogenic effect of bitter tastants in non-CHO solutions.
• Oral administration of specific non-CHO tastants may represent a new strategy to improve short-burst athletic performance.