The effects of menthol on exercise performance and thermal sensation: A meta-analysis.

Abstract

OBJECTIVES\nMenthol is an organic compound with non-thermal cooling properties that has been shown to relieve thermal strain associated with exercise in the heat; however, its effects on performance have not been systematically analysed. The aims were to determine the effects of menthol applied (1) internally and (2) externally on exercise performance and thermal sensation.\n\n\nDESIGN\nMeta-analysis METHODS: A search was performed using various databases in August 2018. The studies were screened using search criteria for eligibility. Thirteen peer-reviewed articles were identified for inclusion in a primary analysis on the effect of menthol on exercise performance; subsequently eleven of these articles were included in a secondary analysis on the effect of menthol on thermal sensation during exercise. A sub-analysis examining the application method was also performed.\n\n\nRESULTS\nMenthol improved overall exercise performance (Hedges g=0.33, 95% CI -0.00, 0.65 P=0.05), demonstrating greater effects when applied internally (Hedges g=0.40, 95% CI 0.04, 0.76, P=0.03). Thermal sensation was also lowered overall across all studies (Hedges g=-0.54, 95% CI -0.67, -0.42, P<0.001).\n\n\nCONCLUSIONS\nExercise performance can be improved by application of non-thermally cooling menthol, which also reduces perceptual measures of thermal sensation. Internal application appears to be the best strategy to improve performance.