What everyone said.. I would add I also alleviate the problem of a "heavy pack" and a "heavy step".
Have you heard the expression: light on your feet? That is what I do. It might even seem that I dance down slope in the mountains.
I move quickly, and not putting all weight on one step.
My foot placement varies with the terrain (roots, ruts and rocks) especially so.
I don't think I have described well, what I am doing.. I am not walking as I do in town and I do not walk heavily with a thud. I am flexible.