I know wiki is an unreliable source so I also provided a reliable one at the end. Here is a quote from webmd
* Counters the shortening that occurs when muscles are repeatedly used -- as in exercise or a repetitive daily activity -- and keeps muscles elastic
* Increases the range of motion in joints
* Decreases joint pain and stress
* Improves balance, stability, and circulation
* Aids athletic performance, relaxation, and posture
I'm sorry if you think I am being negative I just don't want someone possibly getting hurt because she was told not to stretch. Ask any personal trainer, doctor, or sports trainer and they will tell you how important it is. Yes it does tear your muscles, but so does weight lifting. Every time you lift weights you tear your muscles, that is how they get stronger.
I see what the guy you were talking to is talking about now.
http://www.nytimes.com/2008/11/02/sports/playmagazine/112pewarm.html Stretching is still good before working out just not the sit and hold kind. You still need to loosen your muscles and increase your range in movement but in a different way. In the article it has better ways to stretch rather than "static" stretching. But I can really feel the difference playing soccer this term. On Mondays I am always really stiff during the warm-up jog and half the time it hurts my knees and I typically don't play as well, but latter on the week once my muscles have loosened I am able to run and play much better.
So he was right, static stretching may be bad (it is still being debated,
http://www.dailymail.co.uk/health/article-1043690/Fitness-news-Is-stretching-bad-you.html says it may be good for regular exercisers) but that doesn't mean that you should stretch at all. There is nothing about stretching at the end of workout routines so I am going to assume that satic stretching is still alright for that. Things always seem to change so rapidly.
I actually kept reading on that first article and found this
A major study published earlier this year by the Centers for Disease Control, on the other hand, found that knee injuries were cut nearly in half among female collegiate soccer players who followed a warm-up program that included both dynamic warm-up exercises and static stretching.
So what they are saying is don't only stretch and expect that to be enough. You also need to warm up before you stretch. Your muscles need to be active a little before you start stretching.