Tragic Exercise Face - Do You Suffer From It?

I came across this post at Lemondrop about Tragic Dancing Faces, and I have to admit, I'm totally guilty of plenty of them. And no, I'm not ashamed -- it means that I'm really getting into it and enjoying myself. Why be ashamed of that?

However, it got me thinking about the faces I make when I exercise, which I know aren't pretty. When I'm running at a comfortable pace, I like to think I look serene and in control (although it's entirely possible that, to passersbys, I look to be on the verge of death). But, when I'm running hard, or taking part in a hard exercise class, I do some pretty ugly stuff with my features. And, unfortunately, there are all too often mirrors available for me to view these faces firsthand.

Still, as with the dancing, I don't really care. I know I'm giving my all at the gym, and if it means I make some crazy (or hideous, or tragic, or goofy) faces, so be it. How about you? Are you aware of making any really crazy exercise faces? What tends to bring it on?