Oh I am not talking about guys rubbing up against women! That is a completely different phenomenon! This isn't really sexual so much as dominating-- it's shoving body parts into your space in an attempt to make you shrink your personal space. And yeah, adopting a masculine posture can go a long way to eliminating that.

I don't think it's the same as truly being a large person and needing more space than a little seat gives you-- bigger people tend to be more self-conscious of their space and try to compensate for it. But when a 5'7" dude is taking up his seat and half your seat it's like, wtf.