Chronic lumbar muscle strain is mainly due to the following reasons: 1, acute lumbar sprain, untimely treatment, improper treatment methods. 2, long-term repeated high-intensity activities resulting in lumbar muscle injury. For example, prolonged sitting or bending, upright position when holding heavy objects, can make the lumbar muscle in a state of high tension for a long time, resulting in chronic lumbar muscle strain. 3, chronic lumbar muscle strain and climate environment also has a certain relationship, the temperature is too low or humidity is too big can trigger or aggravate lumbar muscle strain.