Run them around before they get to school?

This was done in my elementary school... most kids arrived 10-15 minutes early and milled around outside of the building. Teachers would open the doors at a set time to let us in...

They've reduced recess time down to almost nothing. Even for kindergarteners. Ours gets (well, got) about half an hour, and this is full-day kindergarten, none of that half-day stuff. Also they've gotten really lazy/risk-averse about letting kids go outside if it's a tad cold, or a tad drizzly, or a tad snowy, which it is, you know, a lot of days, so then they just have no recess.

How much ADHD is ADHD and how much is humans and especially kids aren't supposed to sit still so damn much and one of the ways the universal ill effects of this manifest is as ADHD symptoms in a lot of people?