Working out/building muscle

M (23) stage 4 but not on dialysis. I have always been under the assumption that building muscle is bad for you if you have ckd because my nephrologist mentioned something about protein leaking into urine from muscles a few years ago (I kinda forgot what he said exactly). Obviously I can’t eat a ton of protein or take any type of muscle building supplements, but is it actually bad to build muscle with ckd from just working out?