The best place to place the pillow when sleeping is not at the back of the head, but should be placed in the position of the cervical spine. If the pillow is placed in the back of the head position, the cervical spine is in a suspended state, cervical spine muscles and ligaments, there is backward hyperflexion and tension, long-term past neck muscles are not relaxed, cervical lordosis is not improved, the vertebral sequence is still unstable, the neck meridians, blood circulation is still not smooth, as shown after waking up still accompanied by stiffness, dizziness, weakness of the neck. However, if the pillow is too far down, the whole head will fall outside the pillow, the neck backward posture is not a very comfortable posture, often also leads to dizziness and discomfort. The best sleeping position is that the pillow should hold up the back muscles of the neck intact, making the best relaxation of the neck muscles.