In terms of weight training, it involves low loads (~20-30%) (110 lb. power cleans, etc.). They also perform squat jumps with low weight and plyos.
In terms of sprinting, from what I've seen they sprint often. They race a good bit in practice from what I've seen, and I would expect that to be excellent in terms of direct improvement as well as highly taxing. I know that everything is planned into a yearly progression.
If you looked at their training plan, you may think that the volume isn't too high, but the intensity of the sprinting performed (with world-class sprinters running beside you) taxes enough to balance things out.