My recommendation is..
Pilates - great for strengthening the 'Inner core' and...
A pair of reclining seats from Allon White. Over 3 years now and get better all the time. memory foam, heated and great lumbar support (adjustable). Transformed my back problems. I had fixed back seats. Tapering the original seat mounts helped but new seats cured it. Over 12,000 happy miles.
