Hi I had Nissen surgery 5 weeks ago and I would like to know when I can do stomach excersize I feel bloated and I want to tighten those muscles. Thanks Michelle By the way I am 47 years old and I have lost 12lbs since the surgery but I m not complaining because I was over weight. I want to take advantage of weight loss and hope to lose a little more.(10lbs) my stomach feels like I have no muscle control to hold it in. And when I try there is a pulling around the belly button.