The concave sides of female buttocks may be caused by contracture of the gluteus maximus, which is mainly due to frequent drug injections in the buttock muscles during childhood, or women who are usually sedentary for a long time. When contracture of the gluteus maximus muscle occurs, it will cause most of the muscles in the buttocks to adhere, and the concavity will form the symptoms of concave sides of the buttocks. If drugs are often injected into the buttocks, the muscles will be stimulated for a long time, which will also cause contracture of the gluteus maximus, resulting in concavity on both sides. If women are sedentary for a long time or suffer from lumbar disc herniation, it will cause blood circulation disorders in the buttocks due to compression, thus causing muscle atrophy, which will cause concavity on both sides of the buttocks, and the concave skin is dark in color. Usually you should do more outdoor exercises, such as jumping rope, climbing mountains, do not sit for a long time, you can also do yoga to lift the buttocks.