Carbohydrate Rinse Fails to Enhance Cycling Performance or Alter Metabolic and Autonomic Recovery in Recreational...

Area of Science:

• Exercise Physiology
• Sports Nutrition
• Autonomic Function

Background:

• Carbohydrate mouth rinsing is a strategy to potentially enhance endurance performance.
• Its effects on autonomic and metabolic recovery post-exercise require further investigation.

Purpose of the Study:

• To investigate the impact of carbohydrate (CHO) mouth rinsing on autonomic and metabolic recovery.
• To assess the effect of CHO mouth rinsing on cycling performance.

Main Methods:

• Ten male recreational cyclists participated in a randomized, double-blind, placebo-controlled, crossover study.
• Participants performed a cycling trial with either a CHO or placebo (PLA) mouth rinse.
• Measurements included heart rate variability (lnRMSSD), respiratory exchange ratio, and plasma biomarkers (epinephrine, norepinephrine, insulin, glucose, FFA, lactate).

Main Results:

• CHO mouth rinsing did not significantly improve cycling time to completion compared to placebo.
• No significant differences were observed in autonomic recovery markers (lnRMSSD, epinephrine).
• Metabolic biomarkers (FFA, lactate, glucose, insulin) also remained unaffected by CHO rinsing.

Conclusions:

• Carbohydrate mouth rinsing does not appear to reduce the acute sympathetic response post-exercise in recreational cyclists.
• This intervention does not lead to performance improvements in cycling time to completion.