For some reason, when I run shorter distances at top speed (ie. open 5km or 10km races) i tend to tilt my head skyward during the last half of the race as i'm trying to hold my pace. I realize that this is something that many people do to some extent but it seems for me it's pronounced...to the point where people are pointing it out.

For some reason i have trouble avoiding this. During my last 10ki tried to level my head but it feels like its affecting my pace when i do so - something about my breath, so i gave up. Anyway, i'm wondering if

(a) there's a good reason that this happens - ie. weak muscles, genetic, running beyond my limit, etc.
(b) if there's anything i can do to fix it, and
(c) if it's having an impact on my time.

On average i'm about 38min for a 10k.

This seems like a troll post because it's so ridiculous but something that i've thought about asking for a while.

Thoughts? Does anyone do this or see this?

BQ