You know what I love about a good run? It makes your whole day feel better. Not only did you run, but you ran well. That makes it easier for me to suffer through students not knowing what the word "depiction" is (the guy couldn't pronounce it either) and it makes it okay that half the class forgot to read the assigned story. That's how it was yesterday for me. I thought "Alright, they don't listen to me, but hey, I ran four miles this morning, I'm having a good day."
I guess that's why we all love to run because it can make us feel so good, and that's why anyone participates in a hobby or sport. It helps us escape from our everyday lives.