Jockology: good (and bad) research into performance mouthpieces


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- Alex Hutchinson (@sweatscience)


I have to admit, I was very, very skeptical when I read this report in the New York Times about “performance mouthpieces” that would instantly boost strength, power, endurance, flexibility, reaction time and so on. Alarm bells ring for me when a researcher offers evidence like this:

Previously she “had been happy with running 10-minute miles,” she said, but wearing the mouthpiece, she consistently ran a mile in as little as 8 minutes. “It was pretty astounding to me,” she said. “I didn’t feel as tired as when I ran the 10-minute-per-mile pace.”

So I figured I’d look into the research behind the claims for a Jockology column, which appears today.

What I found was a surprise — in both directions. There was some surprisingly good research that suggests there may be a real effect here. And there was some surprisingly bad research that any company should be embarrassed to promote. The main research cited by Under Armour to back up the claims for its mouthpiece come from a special issue of the far-from-prestigious Compendium of Continuing Education in Dentistry. And not just any special issue — every article in the issue is written by someone who is either an employee or paid consultant of Bite Tech, the company that developed Under Armour’s mouthpieces. This is not research, it’s advertorial.

Here’s an example of what this means, as I describe in the Jockology piece:

The results are interpreted rather generously. What’s described as “a definite trend for lower cortisol” turns out to mean that cortisol levels dropped in only 11 of the 21 cyclists in the study – barely more than half. A follow-up study of runners in 2009 also failed to find any statistically significant change in cortisol.

On the other hand, there is a placebo-controlled, double-blinded crossover study, funded by Makkar Athletics, that found an increase in vertical jump and power in a 30-second cycling test. So, despite my skepticism, there may be something there after all…

5 Replies to “Jockology: good (and bad) research into performance mouthpieces”

  1. Thanks for covering this topic, Alex. As a longtime employee of Bite Tech, I’ve seen the evolution of the science behind, and the new product category called, performance mouthwear. I thought I’d offer a couple thoughts for your consideration.

    First off, Under Armour only recently became the brand for our sports line of performance mouthwear. Before UA, it was EDGE. We’ve been developing and testing performance enhancing oral appliances since 1995 and have 40+ patents and a long list of studies and research that gave us the legitimate right to make the claims we make.

    Part of the battle for a small company having developed a scientific breakthrough is how you communicate it to the world in a way that gives it a fair shake, as all new scientific claims are and should be met with healthy skepticism. No matter what we prove in studies, the claim can be made that they can’t be trusted because they weren’t independent. But the very nature of good science is that the results we get should be repeatable by anyone. So we encourage independent testing of our products, but we can’t fund or actively participate in it or it isn’t “independent”. So the question becomes; who will independently spend the enormous amount of time and money to verify our claims?

    Our strategy in pursuing research and testing at the highest level was to assemble a team of the best minds in sports dentistry, therapy, physiology and technology R&D. Our Head of Research and Testing of the past 15 year, Dr. Henry Cross III, retired as Worldwide Technical Director for Colgate-Palmolive. I bet there is a household product in your cupboard right now whose patent bears his name. The others who contributed to the Compendium Special Supplement Issue are all world-renowned and respected leaders in the field of dentistry, including past presidents of the American Academy of Sport Dentistry and lecturers who tour the world providing continuing education for dentists and dental professionals.

    With regards to the studies you mention, we’re constantly learning about the biomechanical process that generates the benefits we see with the use of our products. Cortisol production is related to teeth clenching during times of physical or emotional stress. Cyclists and runners may have different personal trends for clenching. Reduction of cortisol levels is just one of the many benefits our products deliver, including reduced lactic acid, reaction times and heart rate, increased physical strength and endurance and better balance and flexibility.

    I’m excited that companies like ours, Under Armour and PPM are generating public interest and awareness of the potential of performance mouthwear. We’ll let the experience of the users speak for the efficacy of each product. In the meanwhile, we’ll still keep working hard on increasing our knowledge of the phenomenon and developing better ways to deliver more benefits through our products.

    The one thing we can confidently say, even if there is skepticism about anyone’s research, is that you absolutely can enhance the body’s performance and non-invasively change body chemistry with the use of an oral appliance with reverse wedge technology, like the one we offer via Under Armour Performance Mouthwear.

  2. @Shaan Sharma
    Thanks for taking the time to comment, Shaan — I appreciate it. And I certainly understand the challenges of getting good independent confirmation of effects that are likely quite complicated. But let me clarify a few of my criticisms:

    There’s a big difference between “independent research” and “advertising.” If you pay a researcher (like the one at Citadel) to do research on your product, that’s fine as long as the relationship is disclosed — and as long as the research is then published in a proper peer-reviewed journal! That’s where the independent verification comes in. I don’t know the details of the business arrangement behind the Compendium Special Supplement, but the way it was presented gave me no confidence that the results had passed through any independent peer-review process. If you have 15 years of research, 40+ patents and a long list of studies, why not subject them to proper scrutiny?

    Of course, even within the world of peer review, there are different standards of journals. Getting published in JSCR or MSSE is more challenging than some of the obscure journals. And there’s a reason for this: there’s a big difference between well-designed studies and crappy trials that a masters student churns out without any real understanding of statistics or trial design. Case in point: if only 11 of 21 cyclists show a decrease in cortisol, you can’t report it as a “definite trend for lower cortisol,” and you can’t explain it by saying they have “different personal trends” unless you hypothesized before conducting the experiment that this would be the case, and offered a physiological explanation of why this should be and how you can predict which cyclists will respond and which won’t. Otherwise you’re just data-mining after the fact, which is utterly meaningless and is incapable of distinguishing between real effects and random chance. Not to mention the lack of proper placebo control…

    You can certainly “let the experience of the users speak for the efficacy of each product.” That’s what the makers of, say, magnetic necklaces do, and they still get lots of buyers (and endorsements from famous athletes like Paula Radcliffe). But the goal of my blog is to examine which athletic claims are supported by actual evidence. There are some very intriguing signs that performance mouthpieces may have real performance-enhancing potential — so I’d love to see that potential put to the test in properly designed, peer-reviewed trials. But the stuff in the Compendium Special Supplement doesn’t meet that standard, as far as I can tell.

  3. Very well put, Alex, and thank you for your response to my comment. We look forward to taking the feedback we’ve been getting like yours and responding with additional published science that will match or exceed the most rigorous standards. Now that we’re visible in the national sports-science community, we want to take all necessary steps to be open and transparent with regards to our progress and science. At the least, we hope to build awareness of the technological advances in the oral appliance category to both improve human performance and reduce risk of concussions. We welcome all questions and feedback and are grateful for the opportunity to stimulate discussion on this topic.@alex

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