Running back pain may be a symptom caused by factors such as lumbar muscle strain and anterior pelvic tilt. 1. Lumbar muscle strain: it is usually due to the continuous improper posture in daily life and the excessive intensity of regular exercise, which causes fatigue injury of lumbar muscles, and the pain symptoms are more obvious in the morning or after exercise. This is a common cause of lumbar pain after running. 2. Anterior pelvic tilt: If you suffer from anterior pelvic tilt, your hip and abdominal muscles will be weak and your lumbar muscles will be tense. In the process of running, the lumbar muscles continue to be tense, which is likely to cause low back pain. It is recommended to pause the exercise and strengthen the rest if you have lumbar pain after running. If the symptoms are not relieved, you should go to the hospital in time to have an examination and clarify the cause of the disease.