I know that not wearing a shirt during the run is a no-no but what about if your jersey has a full front zipper, can you upzip all the way?
Dave in VA
You might need to ask this to TomAnnapolis, but I think that is a gay practice… 
Dave not wearing a top is NOT against USTA rules. (pardon the double negative) Certain races such as IMNA races adopt a no shirt policy and amend the USTA rules.
At most IMNA races you can unzip your top and you will be within the rules. You could always double check with an official in the transition area before the race to be 100% sure as well.
Good Luck,
RF
Oh sure, go right ahead!
Oh… and don’t forget to run on your thong!! 
Legal or not, that’s no the point…
the question here is: is it gay or NOT?
Going shirtless is not gay.
Get over it.