How does strength training helps a distance runner and a sprinter runner?

Be specific please. My legs are kinda develop already especially the calves, glutes and hamstring a little portion of quads and I do wonder why i am not that good in sprinting well in fact i am doing weighted lunges most of the time. So I'm here to ask this question. Be specific with the specific events please.How does strength training helps a distance runner and a sprinter runner?
For a sprinter, the force they can apply to the ground propels them forward faster, if properly trained it would also allow them to have a longer stride. It will not necessarily make someone who is not fast, fast. If over done it can actually make a sprinter slower. A world record holding sprinter in the 50's improved with strength training and so continued it to an extreme level and ran slower. A certain balance must be maintained because strength is not the only factor in running fast.

For a distance runner it is much less important and has more of a function of preventing injuries. Building muscle would work against a distance runner because it would be unnecessary weight to carry around during a race and it would be weight that divert blood and oxygen from the muscles that are necessary.