Lori , Oh.... ok.. that is really for the standing leg glute and hamstring, but could be felt more in the quad OR the hip flexor stretch on the back leg. It was hard to see at the angle I was in. If you saw it from a side view, you'd see it looks a bit like Eve's Lunge on Reformer. The idea is to 'drive' the standing heel into the floor, pull up to standing by engaging the standing leg glute and hamstring (hip extensions). Let me know if that makes sense!
Due to swelling from arthritis in my big toe joints my physical therapist wants me to build up my glut muscles. This was a great class for just that. Thanks so much!