People wonder why they can’t do a whole lot of sit ups and avoid a tummy tuck.  I always tell them, tummy tucks and sit ups are done for different purposes.  Sit ups strengthen your rectus and other abdominal muscles.  All of us should be doing some type of abdominal exercises.  Pregnancy, especially multiple pregnancies, and large babies born to small women cause a separation of the strip-like rectus otherwise knows as “six pack” muscles.  Upon abdominal enlargement during pregnancy, the muscles separate and move to either side like Santa’s suspenders.  The abdominal bulge which results is from the intestines protruding outward.  A tummy tuck not only tightens the skin which has loosened, but also tightens the muscles.  I think that the muscle tightening is the more important of the two.  While pregnancy is the most common cause of this separation, or diastasis, of abdominal muscles, it is also caused by weight gain.  In addition, some women and men are born with this separation.  You might have seen children with round, protuberant little abdomens.  The problem often worsens as they grow up.  Repairing the muscles reverses the problem.  In summary, plastic surgery should not be an attempt to do what proper diet and exercise should do to keep you healthy.  Likewise, diet and exercise have helped people lose lots of weight, but never tightened anyone’s skin or repaired their separated tummy muscles.