Toning Ball Exercises Good Back Toning Exercises?- Mainly Lower Back?

Good back toning exercises?- mainly lower back? - toning ball exercises

I mean the form of, among other things. I have a lot of my muscle tone after my surgery 5 months ago. I have an exercise ball, free weights, you can. *** ***, But I still take care of my knee (I had knee surgery)
and upper back muscles, but especially the lower back and legs. ok, thnx!