Body weight exercises.......back problem

hi all

I am after some advice. I am currently dealing with a herniated prolapsed disc in my lower back. Awaiting nerve block or possible surgery.

I have been doing a lot of walking and swimming front crawl/freestyle which has helped me shift 24lb since new year which is great.

I would like to do some toning exercises which use my body weight. I have a swiss ball which I sit on everyday and have been doing 1 min plank each day.

Any help or advice would be greatly appreciated.