Sitting for a long time and standing for a long time lumbar pain may be related to muscle strain, poor standing and sitting posture, lumbar spine disease, osteoporosis and so on. 1. Muscle strain: when patients stand for a long time or sit for a long time, it will lead to poor local blood circulation, lumbar muscle contraction, inflammatory molecules under the stimulation of aseptic inflammation, but also may lead to lumbar myofasciitis, thus causing lumbar pain. 2. Poor standing and sitting posture: if the patient is standing or sitting in a poor sitting posture, such as crossing the legs, etc., may lead to lumbar muscle spasm and soft tissue lesions, thus causing lumbar pain phenomenon. 3. Lumbar spine disease: if the patient suffers from lumbar intervertebral disc herniation and other degenerative diseases, the lumbar spine pressure will increase in sedentary and standing, resulting in compression of the nerve root, which leads to lumbar pain. 4. Osteoporosis: If the patient suffers from osteoporosis, the support of bones will be weakened in the process of sitting and standing for a long time and the pressure of lumbar vertebrae will be increased, which will lead to lumbar pain. 5. Tumor: if the patient has tumor hyperplasia in the lumbar region or spinal cord, the pressure of the tumor on the surrounding tissues will increase after sitting and standing for a long time, which will lead to lumbar pain. Patients who have lumbar pain after sitting and standing for a long time should take bed rest in time, and if the symptoms are not relieved, they should go to the hospital for consultation in time.