Sitting for a long time the feet numbness of this situation, should be regularly up and moving, try to avoid sedentary, if not relieved in the short term, it is recommended to further check the sciatic nerve and lumbar intervertebral disc whether there is a protrusion of the situation. Because of the sedentary feet numbness there are two possibilities, the first is because of the sedentary compression of the sciatic nerve in the back of the thigh, causing edema of the nerve, so there will be symptoms of numb feet. The second situation is because the muscle pump of the calf after sitting can not start, resulting in blood stagnation in the distal veins, so there will be swelling of the foot, return flow obstruction, which will also appear numbness. In both cases, as mentioned earlier, you should get up regularly or elevate the affected limb to get some relief, but if there is indeed a problem with the lumbar disc or sciatic nerve itself, further examination and treatment are needed.