[QUOTE] Could be a trapped sciatic nerve ... have you had any physio or osteopathy? Or seen your GP, even? [/QUOTE] GP mostly uninterested, checked reflexes(!) and prescribed painkillers. Another GP who I saw for something else referred me to an osteopath for this back thing. Seen here a couple of times, she seems to know her stuff (she was a "proper" GP back in her native Hungary). She bent me about a bit and gave me some exercises. Unlike me, she doesn't think I'm dying or heading for imminent paralysis. Or doesn't /seem/ to think so anyway. Hasn't suggested any scans. [QUOTE] Be careful. Sometimes a more upright position makes things worse, not better, as it focuses more pressure on the lower back under acceleration, whereas a more crouched position can mean you're better braced against the forces at work. [/QUOTE] This is a pretty good point, actually. I've been told that sitting for long periods could contribute to my back issues, but mostly in the upper back, not the lower, where this new problem is. So maybe any riding is going to be less than ideal, assuming I'm sitting on the bike, which is a fairly safe bet. A less upright posture = less weight on the spine. Maybe if I can strengthen my abs (or some appropriate muscles) to take more of the strain, then the normal sprotsbike gripping with thighs posture might not be as bad for me as I assumed. I've been told it's all about keeping the lordosis in the lower back and not letting it curve the same way as one's buttocks. [QUOTE] Tuono? There's one for sale up there ^^^^^ [/QUOTE] I saw the pictures and I don't think it's for me. [QUOTE] I generally find that the first few rides of the year are agony, so I just skull a fistful of painkillers and ride through it, then I find my muscles start to recover tone and my joints seem to loosen up a bit, after a few weeks. I've been told that one day they won't, and that'll be the end of biking for me, but I'll cross that bridge when I fall into the water. But definitely see if something can be done with physio/osteopathy (I favour the latter).[/QUOTE] ^^