I have failed to make any strength gains in the bench press in the last year or so. I recently switched to 5/3/1 from WSB mainly because I have weak shoulders and I really need the military press day. I also switched from gear to raw at this time as well.

I have always had a big arch (pretty much female gymnast flexibility), but I am beginning to think the largely reduced range of motion and reduced stability with the big weights is what's been holding me back. When I bench I am on more my traps, not really my upper back, is this reducing my ability to use my back as a strong platform?

Has anyone else met someone who arched hard all the time and didn't get anywhere?

Any input would be appreciated.