Is There a Difference Between the 80 20 and the Park Run?

The 80 to 20 split is a way of breaking down training into sessions. The majority of the fitness you need for five k running is similar to that of an American runner, so it's not much different. Some athletes respond well to doing two or three days easy, one day hard. And some still really need that two or three Days Easy and One Day Hard Split. But i personally don't think anything atically different is going to happen if you do it 25, 30% harder.