Runner's high

I recently started to think about "runner's high" from the same perspective I look at my drug use and the more I think about it, the more I realize how fantastic is. Aside from maybe falling in love, it's got to be the best high someone can feel. And with a little hard work, you can get it whenever you want.

Fun fact: according to wikipedia, the etymology of endorphin is:

endo- and -orphin; these are short forms of the words endogenous and morphine