Well, everything and nothing.
While the vast majority of runners do wear traditional running attire, there certainly are an abundance of outliers that go against the traditional.
There are races for runners wearing pink bunny suits, Disney characters (Mickey Mouse, Pluto et al), Zombies, hot dogs, cartoon characters, and the list goes on. You get the picture!
Of course, now that October is here, inevitably there are many 5K races for the Halloween season. So be prepared for runners dressed as pirates, ghosts, (again zombies), goblins and any number of indescribable outfits only limited by the creativity of the runner.
Last weekend on one of my morning runs I was passed by a tall, thin young man wearing lime green running tights, a rainbow colored top, pink glasses, and hat. He reminded me of Sheldon Cooper from TV series “The Big Bang Theory” if he ever decided he was going to run. I wasn’t sure if the runner was promoting the LGBT community or just an early tryout for a Halloween costume. In any event, he was motoring right along.
On the other end of the spectrum are the runners who prefer to run without any attire (or maybe only minimal). The best know one is probably the Bay to Breakers in California that has a subcategory for “naked” runners. There are some female runners (non-elite) who, I’m afraid, might cause themselves serious harm in such a race. Also, while many men may have a junk drawer in their workbench at home, I’m not aware of any running attire called “junk drawers” that they could protect themselves with. I can assure you this is not on my “to do” list.
While it’s all in fun and certainly not competitive I think I’ll stick with my mundane traditional wear and continue to be a spectator and enjoy the view.