answered Sep 09, 2010 at 10:13AM
By sitting in the same position, you have either blocked the vascular flow to the organ or vascular/neurological function. When the pressure is relieved, it takes a few moments for the blood flow to return to normal in the tissues, resulting in these unpleasant feelings. If you are having this symptom a lot, you may want to see your physician regarding other problems, such as back problems or vascular problems.