The following are the possibilities of muscle pain on both sides of the waist: 1, long-term bending and picking up things, sedentary, standing, lying and other poor living and working posture, resulting in chronic strain on the lumbar muscles, as well as high-intensity exercise of the lumbar back muscle strength, etc. will cause wear and tear on the muscles on both sides of the waist to produce pain. 2, lumbar disc herniation compresses the nerves that govern the lumbar muscles, which can lead to muscle pain on both sides of the waist. 3, female patients should consider the combination of pregnancy. The lumbar muscles become sore and uncomfortable during pregnancy due to the growth of the fetus and the enlargement of the uterine cavity, and women’s periods also tend to cause lumbar muscle pain. 4, urinary system diseases can also cause muscle pain on both sides of the waist, such as ureteral stones, kidney stones, etc. 5, systemic infectious diseases, tuberculosis, brucellosis, etc., resulting in generalized fever, can also cause lumbar muscle pain. 6, when sleeping at night, not paying attention to Keeping warm, the lumbar area is cooled resulting in muscle spasm, and when you wake up in the morning, you will feel muscle pain on both sides of the lumbar area.