I'm working on my curves
Just to let you know, I went along to a Feldenkrais practitioner. We had a session in which she helped me to become aware of my lower back. I realized that it was a big hole in my body awarness. She gave me some breathing techniques which helped to "wake up" my awarness of the area. Once I became able to sense the position I was able to work out ways to extend the muscles. After a week of regular gentle stretching I am able to touch my knees with my forehead -- a novel experience for me -- and this is beginning to help my rolling.
So, thanks for the tip, afwen.
The exercise I've been doing is very simple. I curl up, bend my head towards my knees, hook my arms behind my knees, and pull gently. This was ineffective before, because I wasn't able to relax and extend the muscles. Now I'm able to feel them better I can get them to extend, and get that "stretching" feeling.
So, it wasn't finding the exercise that was the problem -- it was awareness.
Interesting, huh? (Well, not to you maybe.)