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dgold44
Go surfing! Paddle in a prone position only! First get out of Vegas and move to either the right or left coast.
As for other options. Do back extension, no sissy stuff. Lock your ankles under something and let your body be hanging out over a support ( no support above hips). Then lift you body from the hips vertical and hold for 20-30 seconds, then slowly lower upper body back to horizontal. Repeat
for 15 reps. Once comfortable with 1 set of 15 reps advance to 2 sets.
When I was young (still in my 30s), I did vertical stomach curls. Grab a vertical slant board at the top, then lift my feet from the floor up and over my head, touching the wall behind me with my toes. I was able to do that because of doing 1500 old style sit ups on a slant board every day. So the stomach muscles were so strong that the back was strong also.
My world fell apart when some idiot came along and preached sit ups were bad for your back, do curls instead to be safe.
There is nothing to compare to old school. Just a bunch of softies. I remember the forester fire fighters buckling their lower legs (below the knees) to stakes driven into the ground with leather straps, then arching backwards until their heads touched the ground behind them, then returning to a standing vertical position. That was in Montana though where men were really Men.
Shalom