The Gear Junkie Scoop: Performance Mouthpiece

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By Stephen Regenold

Ironman champion Chris McCormack wears one. So do multiple Olympians and NFL players like Adrian Peterson of the Minnesota Vikings. The new category of sports accessory called performance mouthpieces is certainly catching fire among pros and amateurs alike. These mouthpieces purportedly increase strength and endurance, speed up reaction time, reduce stress, improve flexibility, promote betterbreathing, and quicken recoveryafter competition or training.

Bite Tech, the Minneapolis company that makes the Under Armour Performance Mouthpiece, cites a recent University of Minnesota study that links jaw clenching to stress hormone releases that may inhibit performance. The theory is that clenched teeth, a natural response to elevated stress levels during activity, signal the brain to release chemicals that affect various parts of the body and hold back physical potential. The Under Armour Performance Mouthpiece can help prevent that bad neurological juju, Bite Tech claims. 

Too good to be true? Gear Junkie had to give it a try to find out.

In a dentist's chair last fall, I bit down on some rubbery impression compound as the first step in getting a custom mouthpiece made. A few days later, my Under Armour mouthpiece arrived, a translucent mold of my lower teeth topped with yellow tabs where my molars come together.

It fit precisely in my mouth, locking into the grooves between my teeth and sitting comfortably like a low-profile mouthguard. I went for a long run later that day, and the small yellow tabs on the mouthpiece (Under Armour calls them power wedges) kept my teeth from clenching on the trail.

According to Bite Tech, performance mouthpieces are not a new idea. Centuries ago, the company says ancient Greek athletes bit down on leather straps for an edge during competition. Viking warriors clamped on wood or leather pieces for focus on the battlefield. Under Armour's molded mouthpieces are a modern equivalent.

The cost? Prices vary from $300 to $495 for Under Armour products, depending on the dentist who sells it to you. An Under Armour competitor, Makkar Athletics Group, charges $1,000 or more for its mouthpiece.

Over four months, I wore the Under Armour mouthpiece skiing, cycling, climbing, running, and during a handful of endurance-sports competitions. Bite Tech has dozens of testimonials and claims of immediate strength increases or gains in flexibility and speed. For me, the effect was not immediately apparent. 

But the mouthpiece grew on me. After some use, I realized that I would sometimes grind my teeth when it was not in, a habit that the mouthpiece had brought to light. I found myself missing the mouthpiece when I forgot to wear it on a run.

I can't quantify the mouthpiece's effectiveness. It is difficult to say what it does, and some placebo effect may indeed come into play. But for me, I do notice some stress reduction when I keep from grinding my teeth. That alone increases my comfort and performance at least slightly.

It's harder to gauge the supposed advantages for breathing, strength increase, and the neurological angles. Some athletes have said that a mouthpiece causes immediate gains, but the effect was more subtle for me.

At a cost of several hundred dollars for a little-understood technology, it is hard for me to recommend friends to jump in with the Under Armour product. But for eager early adopters, serious athletes, or exercisers with disposable cash, Under Armour's mouthpiece could be worth a try. A burst of Viking warrior power–or at least less teeth grinding–may be the result. 

–Stephen Regenold writes about outdoors gear at

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