Is there any evidence positive or negative that suggests the use of mouth guards and being able to bite down on them effects training at all? I know some people that swear by them and since I have one for rugby now it got me thinking about if it’s bull or not
Yea there is some data on them:
https://academic.oup.com/milmed/article/183/suppl_1/510/4959938
And others.
To me, it doesn’t seem like it matters either way for powerlifting. Probably better for contact sports 
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