With or without the presence of a diastasis, there is normally a certain amount of shifting of abdominal contents related to change of position. If there is a weakness of the abdominal wall, whether due to a hernia, diastasis or both. A hernia is a true outpouching of the abdominal wall and may include abdominal contents; a diastasis more typically is a larger area of generalized weakness between, and separation of, the paired abdominal muscles, which are called "the abs." So if someone has a large diastasis and shifts position, anything within the abdomen can also shift. None of those, though, should create a problem or pain with a pure diastasis. A hernia, on the other hand, can be associated with acute or chronic abdominal symptoms. If there is any question you should contact your primary care physician and consider a consultation with a general surgeon.I hope that this helps and good luck,Dr. E