Girls practice abdominal muscles only benefits no harm, because the abdominal muscles are part of the body’s core muscle groups, including the rectus abdominis, internal obliques, external obliques and transversus abdominis, when the abdominal muscles contract, can make the trunk bend and twist, the abdominal muscles also play an important role in maintaining the activity and stability of the lumbar spine, can control the activities of the spine, when the abdominal weakness, can not properly maintain the pelvis forward, and can make the lumbar spine physiological increased curvature, leading to disc bulge and other diseases. The only bad thing about practicing abdominal muscles is that there is no good warm-up exercise before exercise and no good relaxation stretching exercise after exercise, resulting in abdominal muscle damage.