Pre running stretches.

I am not an expert, and I know there is a lot of controversy on this topic but I am a dancer and this is just my own personal opinion, .
DO NOT, EVER, go all out for intense static stretching before you run or do any other cardio exercise! Picture this: Your muscles are cold and you are trying to make them stretch- not good! You must warm up your muscles before intense static stretching.
It always safe to do dynamic stretching before and static after, but it can also be good to do really light static stretching with your dynamic stretching.
For example, before I dance I usually do my dynamic stretching and then for static stretching instead of putting my palms or elbows on the floor, I only reach a little past my knees, and instead of the full splits I only go about halfway down. So basically my advice is this: Always stretch BOTH before and after- dynamic and light static stretching before and intense static afterword.
Hope this helps!