I've found that stretching helps, alot. I also try to make sure I have good shoes, I find that more support is better. There's a store off of Rt7, not far from Tysons - is the the little strip mall across from Freshfields, forget the name. They'll hook you up. I also try to Run/Workout on softer surfaces, like a treadmill, over a concrete sidewalk. I used to get them when I played soccer, but, that is all about shoes with little to nothing between you and the ground.