Help me with my sore back, please

[sp9]

Every few months or so I pull someething in my lower back and it hurts like hell for a week or so, at the beginning it can be so bad that it hurts just to stand up and I feel like an old man trying to walk.

What are some good stretches or moves to get my lower back in better shape?

How do you feel about hyper extensions, superman stretches, bridges, etc. and any thing else you could add??? The first time I hurt it was trying to muscle up one last rep on squats and putting my back into it, the last time I don't know what I did.

Any suggestions or experiences you could share would be helpful. I don't think it is a disc problem, more of a muscle sprain that is gone within a week.

Thanks.

[BIG TEXAN]

Everyday as aprt of my warm-up routine I do 3 sets of 12-15 on back extentions(spelling). Since I've been doing this I hardly ever get a sore lower back. As for stretching, it's like doing toe touches but pulling your chest into your knees instead of reaching for your toes seems to help strech my lower back.