Running On Sand vs. Concrete

I'm blessed enough that I live right next to the beach. So when I go running I do my first 1 or 2 on the concrete and then for a change of scenery I do the second half on the beach it's self. So I was interested in finding out what the difference to the body is.

Running on Sand is more intensive, and easier on the knees.

Full article:

http://www.fitday.com/fitness-articles/fitness/exercises/sand-running-vs-running-on-concrete.html#b