Walking too much back pain may be related to excessive lactic acid, lumbar muscle strain, lumbar disc herniation and so on. 1. Excessive lactic acid: Walking will involve the muscles of the lower back, the muscles of the lower back itself is relatively weak, in the fatigue or walk too much lactic acid may accumulate, resulting in muscle fatigue, lumbar pain. 2. Lumbar muscle strain: after walking too much or overuse of the lumbar muscles, the lumbar force is too long, when the lumbar back muscle strength is weak, long time pulling. When the load is unbearable, it will lead to muscle strain and produce pain. 3. Lumbar intervertebral disc herniation: when standing for too long or bearing weight for a long time, there is disc degeneration or slight slipping. If you walk for a long time, the herniated disc will be aggravated at this time, stimulating some of the surrounding muscle tissues and fibrous ring tissues, which will also cause pain. When there is walking more back pain, it is recommended to consult a doctor in time, with the help of the doctor to clarify the cause, targeted treatment or therapy.