Not wishing to divert from the substance of Tom’s article, but heck… I’ve a good friend who was knocked off his moped in London 5 years ago. Serious head injuries and long term consequences. He’s always been a driven character, high achiever, keen outdoorsy. But this thing knocked him right back. He’s always run a bit, but in the last couple of years taken it more seriously (and with some seriously big achievements). He bikes as well, but running’s his thing.
Anyway point being, he credits exercise with rewiring his brain, clearing the static and letting him function at a fairly normal level. It’s good for us sure, we all know that, but I think he shows that it’s deeper than that. More than just a bit of a distraction for a couple of hours.