I lack a great deal of spinal strength and mobility. The Thoracic Bridging program is almost un-do-able.
The most success I remember having is when incorporating more of the Reverse Hyper variations and Back/Spinal Extensions in my programs.
Is there a (if not, why not) Arch Body/Back Extension exercise table similar to the F1 Hollow Body programming? I do see elements in later IM but wondered why it's introduced later rather than sooner.