Lying more back pain may be a long time in a fixed position, lumbar muscle fatigue injury and other physiological reasons, may also be lumbar disc herniation, lumbar spondylolisthesis and other pathological factors. 1. Physiological reasons: lying for too long will cause the lumbar muscles to be in a fixed position for a long time, resulting in the lumbar muscles being in a state of tension for a long time, unable to be completely relaxed, resulting in fatigue damage to the muscles and the symptoms of lumbar pain; in addition, lying for too long will result in the lumbar muscles being under pressure for a long time, which affects the blood circulation of the lumbar muscles, and the above symptoms may also occur. 2. Pathological factors: lumbar degenerative diseases lead to lumbar intervertebral disc herniation, the stability of the lumbar spine will be reduced, the intervertebral disc protrudes to the back or side of the posterior, on the nerve roots or spinal nerves to produce compression, there may also be lying too much lumbar pain; lumbar vertebrae around the soft tissues of the lumbar vertebrae for a variety of reasons lead to the decline in the ability to maintain the lumbar vertebrae, resulting in lumbar vertebrae slippage, the above symptoms may also occur. There may also be other causes of back pain when lying down too much, so it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy under the guidance of the doctor.