Runners consistently buy the cushiest, most supportive shoes they can so there will be less impact on their joints. This is the same reasoning as people who run on soft surfaces to avoid impact. Regardless of the whether people run with 10" of foam under their foot or run on grass, ONLY THE PAIN IN BLOCKED, NOT THE IMPACT. Your joints will still get rocked and rolled if you run with poor form on any surface, no matter what you have on your feet.
Good running form eliminates unnecessary joint impact, and allows for a smoother, more efficient stride. So what is proper running form?
Pose running is the most efficient, least impacting, and fastest way to run. Hands down. To learn more about Pose running, check out my running page and start down the road to pain free running!