Menthol use in Athletes

Posted by Russell Best on 17 Oct 2017 EXERCISE, SPORT, TRAINING

Mint Leaves
Something I came across several years ago was early research into the use of menthol as a cooling agent for athletes. This sparked my interest and has led me to undertaking my PhD research into how menthol could be used to enhance athlete performance by affecting the way athletes perceive heat.
One of the hindrances to athlete performance is fatigue caused by over-heating (especially in warmer climates). As a runner myself, I’m more than familiar with the feeling of over-heating, and like most runners, have felt the burn of fatigue it can bring on. Keeping cool by drinking water or electrolytes is the standard method that athletes use to try and reduce or delay over-heating. And it’s effective up to a point.

If we can find a way for athletes to feel cooler before or during exercise for longer, they’re likely to be able to perform better because it will take them longer to feel fatigued. 

Something I came across several years ago was early research into the use of menthol as a cooling agent for athletes. This sparked my interest and has led me to undertaking my PhD research into how menthol could be used to enhance athlete performance by affecting the way athletes perceive heat. 

What is menthol? Menthol is the natural oil and alcohol found in mint. You’ll find menthol in a range of products such as throat lozenges, mouth wash and peppermint tea

The theory behind the use of menthol is that by taking it orally, an athlete feels like they can breathe easier, and feels cooler; and is therefore able to increase their output. (Output increase can be measured by running faster, cycling further, or hitting harder, etc).

So far, the research shows that most athletes (up to, but not including elite athletes) report that exercise feels easier, that they are able to go faster and further, and are able to stay cooler for longer when taking menthol (we’ve tested it with lozenges and liquid format). 

This is where the research got interesting: menthol use seems to have a neural rather than a physiological effect. So although athletes feel like the menthol is cooling them, actually when we measured the results, it’s not. Here’s what’s really going on: The use of menthol sends a signal to nerve endings that you’re being cooled, this creates a mismatch between actual temperature and perceived temperature, meaning that athletes feel like the menthol is cooling them, and therefore push themselves further and as a result their output increases. 

You might think this means that menthol is a placebo, but it’s more complicated  than that because it’s something we can actually measure. 

The next stage of research we’re working on is trying to determine whether if people know that the menthol is causing a neural (rather than physiological) response, they still have an increase in output. 

What we also think is that menthol use may be less effective on elite athletes because they are trained to deal with the heat. Whereas if someone is not physically fit, menthol use could be more useful, because they feel hotter faster, and find exercise more challenging than someone who is an elite athlete. 

In our biokinetic clinic at Wintec we’re thinking about how we can apply these learnings to help people who have just given up smoking to start and stick with an exercise plan. We’ll keep you posted on our findings.

In the meantime, why not give it a go yourself. Try drinking some peppermint cordial or sucking on a menthol lozenge before and/or during your workout and see if you notice a difference in your output, and then compare it on another day without.

About the Author

Russell Best

Russell Best is an Academic Staff Member at the Centre for Sport Science and Human Performance at Wintec, and Nutritionist at the Waikato Human Performance Hub. Russell is a PhD candidate and has worked as a nutritionist and lecturer in the UK and New Zealand.