How to build atrophied back and ab muscles

[MarcosiasP]

My back muscles atrophied due to the hypersomnia i suffered for 6 years. my back and ab muscles had atrophied from practically being bedridden. Ive tried working out in the past years but i cant seem to activate these muscles for when I do lat, rhomboid, and ab workouts but I always end up with only sore arms and pecs. I believe my arms and pecs unconsciously take over where the weak muscles would not pick up, for it was no problem to work out any of these muscles before my issues. Maybe somehow its throwing off my form; regardless, it is messing with my motivation to lose weight. Anybody no how to help me fix myself? a third of my paycheck at my chiropractor obviously is too much

[SuffolkPunch]

Your arms and pecs can't perform pulldown, pullup or rowing movements on their own.

Sometimes you may not feel a muscle working but it is.

Just focus on the movements I mentioned. Keep good form and full range of motion. Select a weight that causes you to reach form failure after maybe 8-10 reps.