I stretch at the end of a workout not before. I find that warming up slowly on the treadmill is better than stretching before. Also, staying hydrated is important, as one is far more likely to pull a muscle if not properly hydrated. However, if you are a competitive athelete, I am not sure you should avoid stretching before competition. I know I stretched before track meets carefully.Quote from ShoeshineBoy:
Stretching has been shown to relax the arteries which is always a good thing.
The studies have also shown that stretching before a workout can decrease power and strengh, generally a bad idea...
The more explosive the movement though, the more likely that you are to pull a muscle, unfortunately. I find that my body will tell me to slow down by giving me hints that I am about to pull a muscle if I progress slowly. But if I just went out and ran a 50 explosively, it would simply retaliate with excruciating pain if I pulled a muscle. Anyone that has ever pulled a hamstring or groin muscle knows the writhing pain.
That is why if you need to develop fast twitch muscle fiber like a sprinter, you should train to do so, imo
http://en.wikipedia.org/wiki/Ballistic_Training
