Lower cross syndrome, also known as pelvic cross syndrome, includes a posterior tilt of the pelvis and an anterior tilt of the pelvis. The main cause is a change in body weight due to prolonged standing or sitting, which causes the pelvis to tilt backward or forward, causing low back pain and pain in the popliteal fossa of the knee. The anterior tilt of the pelvis is mainly due to the shortening of the iliopsoas muscle and the rectus femoris muscle in the quadriceps, while the posterior tilt of the pelvis is due to excessive tension and shortening of the gluteus maximus, hamstrings, and rectus abdominis, which pulls the pelvis forward and upward, thus causing the pelvis to tilt backward. For the pelvis to tilt forward or tilt backward, usually pay attention to functional exercises, mainly for the muscles that affect the anterior and posterior tilt, so as to reduce the symptoms of lower cross syndrome.