You should never stretch before any activity (not even yoga). The body doesn't respond well to this and stretching before the body is warm can lead to serious injuries.
The best way for a runner to warm-up is to do mobility drills (leg swings, cariocas, scoprions, you can find tons of useful info about this on youtube).
After a good warm-up they should start at a medium pace and then run faster once the body feels ready to go.
But runners are a funny breed of exerciser. They never stretch and only do it kicking and screaming when their bodies are completely broken down and injured so badly they can't run anymore.
Every runner I know (and I know tons of them) has such poor flexibility and hip/knee/back/foot issues. They rarely bother with maintenance which is so important for such a high impact sport.
If you're an experienced runner and you lay off for a while it's key to start back up super easy. Shorter slower runs. One of my best friends at work has had to do this several times because of nagging injuries.
Head over to runner's world and just type stretching into any search bar. I think you'll be pleasantly surprised at what you find. Good luck with your book : )
Last edited by ExerciseEditor; 02/19/10 08:12 PM.