Menthol Mouth Rinsing Maintains Relative Power Production during Three-Minute Maximal Cycling Performance in the Heat...

Area of Science:

• Exercise Physiology
• Sports Science
• Environmental Physiology

Background:

• Menthol's ergogenic effects are established for endurance activities.
• Research is needed on menthol's impact on high-intensity exercise exceeding maximal aerobic capacity, especially in heat.

Purpose of the Study:

• To assess the effects of 0.1% menthol mouth-rinsing on a modified 3-minute maximal test in heat (33°C).
• To compare menthol (MEN), cold water (WAT), and placebo (PLA) mouth-rinses on physiological and performance variables.

Main Methods:

• Randomized, crossover, single-blind, placebo-controlled study with 11 participants.
• Participants completed three maximal tests with different mouth rinses.
• Continuous monitoring of heart rate, core temperature, oxygen uptake (VO2), ventilation (VE), respiratory exchange ratio (RER), and cycling power. Thermal comfort, sensation, and RPE were self-reported. Blood lactate (BLa) measured pre/post.

Main Results:

• Menthol mouth-rinsing demonstrated small to moderate effects on relative power output towards the end of the test.
• Participants using MEN maintained higher relative power for longer durations compared to WAT and PLA.
• Specific significant differences observed between 75-105s, 105-135s, and 135-165s intervals.

Conclusions:

• 0.1% menthol mouth-rinsing offers small performance benefits for short-duration, high-intensity exercise in hot conditions.
• Menthol may enhance power output maintenance during intense exercise bouts.
• Further research should explore menthol's mechanisms in heat and high-intensity exercise.