Ask a fitness expert how to practice the two lines from the abdomen to the lower body.
Hello, the two lines you are talking about are groin, and there is no muscle groove between the external oblique muscle and the leg.
As long as the subcutaneous fat content is reduced, it will naturally show up. You can practice more abdominal muscles (rectus abdominis, oblique abdominal muscles, transverse abdominal muscles), and then do some aerobic exercise to reduce fat.