The arrows point to the borders of the recti muscles. Inbetween is a weak area. Contrary to popular belief, doing sit ups will just strengthen each individual muscle, but not bring the muscles back to the middle again.
When standing, the immobile insides of the abdomen (that’s fat and intestines) will shift and create a bulge. That bulge is not related to the subcutaneous fat that is treatable with liposuction or laser liposuction. Unfortunately, a significant diastasis does not have any minimally invasive options to repair, but requires a tummy tuck instead. In an obese person, the bulge will reduce with weight loss because the fat that surrounds the intestines becomes less heavy.