Low back pain is more painful when bending, the reason is mainly due to the following aspects: 1, due to lumbar disc protrusion, after the protrusion is formed will be to the surrounding to peripheral nerve irritation, so it is easy to appear pain symptoms. The pressure between the vertebrae increases when you bend over, resulting in a more pronounced squeeze on the intervertebral disc, which may lead to increased stimulation of the peripheral nerves, resulting in a more pronounced pain. 2, due to strains of muscles, ligaments and other soft tissues in the lumbar region, bruising and inflammatory edema will occur after the strains, which will also lead to pain, and when you bend over, it will lead to local injury lesions 3, the lumbar degeneration, osteophytes and calcification, will produce force extrusion of the surrounding soft tissues, pain, when bending, will lead to local stimulation of the surrounding soft tissues further intensified, resulting in more obvious pain.