4-5 am back pain and the following factors: 1, may be related to cold, sleep at night if you do not pay attention to warmth, cover the quilt is not tight, will lead to the waist cold and wind, this situation will lead to local meridians and pain, this situation is generally through the warmth, hot compresses can be significantly relieved. 2, may also be related to sleeping posture is not correct or waist injury and other factors, this situation with the Sleeping lumbar squeezed, or lumbar previously injured have a great relationship. 3, may be too soft with the bed, which is very common in daily life, many people sleep too soft bed will appear after lumbar pain, this situation is mainly due to the lumbar muscle relaxation during sleep, if the bed is too soft, the lumbar can not be supported, due to the lumbar vertebrae position of the movement of the nerves caused by the compression, the emergence of pain phenomenon. Pain phenomenon.