I don't see a direct link between exercise and stage fright...

But, I do feel better generally when I'm doing regular exercise - there may be something to regular exercise making it easier to process some of this stuff...

I'm with the others though - you do it, you throw up.. next time you do it you throw up a little less. I first played guitar in front of a crowd almost 20 years ago, and I still get the shakes before a gig... and beer makes me feel worse...

I just have to grit my teeth and do it. After the first tune I'm rocking out on my own and barely care what the audience think anyway... :D