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>>>Incidentally, why do gridiron players paint black stripes across their cheeks, under the helmet?
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>>To deflect sun rays. I don't know the exact science of it, or if there really is a scientific basis, but that's why they do it.
>
>It doesn't so much deflect the sun's rays as absorb them so it doesn't reflect into the eyes. Overall, it makes it a bit easier to concentrate on the job rather than the sun. Not tons, but a bit.

Yes, I'm constantly blinded by the sun reflecting off my cheeks. The good Lord has a lot to answer for in such a design flaw - NOT!

Why is this impotant to gridiron players (who presumably have a lot of the light intercepted by their helmets anyway) and not to, say, baseball, cricket or footy players?

Maybe it's because so many of these players are neanderthals, with over-developed, reflective cheek bones. But doesn't the deep set of their eyes, under the accentuated brow ridges, provide protection? :-)