I am quite slim. I have relatively toned upper and lower, bearing inning I have done hardly any exercise for a long time due to back problems. I Am back exercising, and toning well, stregnething muscles as I want. But as I am getting fitter, I am not touching what is now becoming a prominent overhang. I am using the cross trainer, and swimming. I am doing core strength exercises, but I can't do twisting exercises yet.
What do I need to do to get rid of this fat/tone it?