Even though it was dark, I went down and did a few sprints on the golf course tonight. It was cold out, but it was quiet and still. It felt good to be surrounded by nature and little other noise.
I would think this type of activity is very, very good for the nervous system. After all, we are built for nature, not urban living. It's refreshing to go someplace where you can "turn off" your nervous system for a bit.