The Influence of L-menthol on Time Trial Running Performance in Recreational Runners

ABSTRACT

Purpose: This study investigated the effects of combined mouth rinse and topical application of L-menthol on perceptual responses and running performance under thermoneutral conditions (22 ± 2°C and 30–60% relative humidity). Methods: Twelve recreational male runners (age: 31.7 ± 3.8 years; age range: 27–39 years) completed a familiarization, a control test (CON) and two maximal 10-km time trials (counterbalanced randomized crossover design) performed in different days with a non-thermal cooling intervention (combined application of a L-menthol mouth rinse and topical L-menthol gel - MEN) or placebo (PLA). Performance and perceptual measures (thermal sensation, thermal comfort, ratings of perceived exertion and affective response) were recorded for every km completed in the 10-km test. Results: Performance time was lower in MEN (P = 0.03) and PLA (P = 0.003) compared to CON, but no differences were found between MEN vs PLA (P = 1.00). All perceptual responses increased over time in all conditions (P < 0.0001), but only the thermal sensation was lower (P = 0.01) in the MEN compared to CON. Conclusion: L-menthol strategies promote fresh sensations and may improve running performance in 10-km time trial in recreational runners, but the performance improvement could mainly be due to a placebo effect.

KEYWORDS:

• Endurance
• performance
• running

Acknowledgments

The authors thank Francisco Teixeira Coelho, Markus Vinícius Campos Souza and Eduardo Henrique Tavares for their technical support and assistance and all the volunteers who gave their time to participate in the present study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Informed consent for human participants

Informed consent was obtained from all human research participants and approval for the study was obtained from Human Research Ethics Committee of the Federal University of the Triângulo Mineiro (UFTM; CAAE: 01711018.8.0000.5154).

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES DS/CAPES), Brasília, DF, linked to the Ministry of Education from Brazil.