Originally Posted by
wphamilton
I don't know about an exercise but I've found that consciously straightening my back by tilting the hips more forward relieves that pain when it crops up. After a good layoff I suspect that I'd be curving my back at first, which starts to be an issue for me after about an hour. Since you've done it before, I'm guessing that after you limber up and get your form back you'll be ok.
+1. I have a pretty sensitive lower back. Regardless of what I do, I'm probably going to end up injuring myself once a year or so and nurse myself back to health for a couple weeks (I've yet to injure it by riding my bicycle though).
But I also deliberately try to straighten my back. I remember a lesson I read from Lance Armstrong that recommended dropping your belly towards your knees. I find that a good way to think about it. When my back starts feeling tension or pain I remind myself to do that and it immediately feels better.