You're going to get a fair amount of disagreement about this. Easy running is, as far as all the resources I've ever seen or been trained in, running that actually *is* easy to do. It's a relative effort level. The challenge will be for very new runners for whom no intensity of running "feels easy". For them, a walk/run program to build fitness is pregnant called for. Eventually people can get to a place where their "easy" intensity work is actually at a running pace. Cycling is also good!