You find a packet of energy gel in your purse. And I'm a runner who doesn't even use gels, just get the occasional freebie.
You're willing to spend more on running shoes than you spend on work shoes. $110 to try a pair of Altras? Sure! $25 for a pair of nice black flats for work? Eh, I'll wait until they're on sale.
You own more running shoes than other shoes. Basically I have a pair of black flats and a pair of black heels for work, and the rest of my shoes wardrobe is for running.
The most obvious tan line you have is on your wrist from your Garmin. And then it's exacerbated by the RoadID, and if you add in a Fitbit... well then you're just out of luck altogether. I tried to fill it in for the wedding with self-tanner, and ended up with some weird orange-y blurry lines around the edges. Fortunately, I don't think it was really visible in the photos!
The next most obvious tan line is on your calves from your running capris. I feel self conscious in knee-length skirts, afraid someone will think if I just have strangely-colored knee high stockings on.
You socks come with a 9-step wearing guide. I can't remember which brand of compression socks this was, I ended up not really liking them and no longer have the socks (or instruction manual).
You plan your weekend around your long run. Well, of course!
What makes you a runner?