Exercise as a patient is a popular subject which reminded me of a recent experience.  If you have ever been a runner you likely know of what is called the "runners high".  It is a feeling of euphoria brought on by the release of endorphins.  Running is mostly hard work but occasionally it is magic.

There is a greenbelt along the river where I live that bikers and pedestrians enjoy.  It is really quite a nice amenity.  It is local custom for bikers to signal with a bell perhaps or more commonly to announce "on your left" when passing to avoid startling walkers. 

I was jogging along recently and it was a perfect day.  A gorgeous morning and I felt good.  As I went along everything came together.  I was the winged god Mercury floating effortlessly through space with the wind and gravity paying me hardly any mind as I flew past.  A glorious experience that I would gladly become addicted to. I could have run all day with no effort at all.