If you want to see the damage that a desk job can do, teach squats to a group of adults. Many of us spend our days sitting at a desk, drive in a car for an hour or more, sit on the couch for a couple of hours, then curl up in bed...with our hips at basically the same angle. Those of us that are active might throw in an hour of weights or time in the rock gym, but it’s hardly enough to balance the time spent in the seated position. As we sit, our hip flexors (primarily the iliacus and psoas major) are held in a shortened position, while the hip extensors (glutes in this case) are held in an artificially lengthened position. Over time, this position becomes “normal” for our hips, and we begin to hold a similar position even while standing, relying not on our bones to maintain erect posture, but the muscles of the back.