hitting that Zone 5 briefly is a good nervous system reset

I ended up doing this inadvertently earlier this week due to some medication side effects (yay akathisia!) making me want to go outside and just seriously run fast, including up the nasty hill nearby. Which I could, so I did. I'm amazed at how much it seems to have helped, for how simple it was. (Another one from the past, though for different situations: alternating hot and cold showers.)