Too many of us are obsessed with  flexion driven back disorders. Which  is fair because most cases of back pain  are flexion based.  However, not all of them are. Some are because you are over extended, and frankly, you need some  careful flexion in your life, and back.
Until I produce a good guide, here are some useful thoughts  from
https://tonygentilcore.com/2014/01/extension-based-back-pain-b/
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