well the less you carry you tank the better it will be. i put my tank near the entry point most of the time i gear up in the water. I even carry the tank in a small folding cart to the dive site.i’m still pretty young but i would not say that i am strong. i’m now using a drysuit and steel tank plus a lot of weight, and man its heavy! in the future i would like to go to doubles, but i think i would mess up my back if i did that right now. does anyone have some exercises they recommend to strengthen their lower back or back in general to help prevent injuries from diving? i want to be physically fit for diving and looking at the big picture to still be diving without problems as i get older.
Core training, strength training don't use weights.