What bike do you ride? Have you tried something upright? Maybe a riser stem if flipping doesn’t help.Reading on here - I don't actually do that many miles ! - I get up to about 100 a week in the summer months. Club training rides are 33 miles on Sat - and club runs 60 sun (I tend to do one or other!) - Right now 25 miles once a week and I would be happy with that.
Its the delayed pain - which makes it difficult - If I got on the bike and it hurt then of course I would stop - but the onset seems to be later - so never sure if it is the biking.
I would reluctantly quit cycling - but would really hate the resulting weight gain ! - couldn't run - and swimming seems to aggravate my back and neck
I get pains swimming too but my technique (if you can call it that) is atrocious!
do you heat your back and then stretch after cycling?