This muscle is located on each side of the body and it's roll is to stabilize the pelvis and lumbar spine. The muscle is responsible for right and left bending and rotation. Since many of us sit for 90 percent of the day, the quadratus lumborum becomes short, tight, and overused, because each side is constantly working to keep you erect when you sit without lower-back support. Grecian style flowy wedding wear of chiffon
If you habitually cross your legs, quadratus lumborum will become engaged. When you cross your right leg over your left, you will lean slightly to the left, and your right quadratus lumborum must work hard to keep your upper body erect causing fatigue and ultimately pain.