Knowledge Is power...
A few secrets for your lower back Issues.
Work up to 1000 crunches a week slowly, a strong core helps support you taking the load off your back.
Set your fork up a bit on the stiff side and go a bit thick with the rebound damping.
A fast moving quick rebounding fork goes into every little hole, slowing you and will wear you down.
Don't go so slow the fork packs down,,google that one..
The other advantage of a stiffer front end, you will feel most hits soon enough to lift your a$$ to lessen the spinal Impact and this will make your rear suspension(Yer Legs) stronger and faster really fast..
Last but not least, GET A DROPPER POST~~~~~~
Keep In mind that a hard tail will reach Its limits on really crazy trails before a full squish. be careful following a FS trail bike with a good pilot Into the rock gardens at mach 3