I too, was suffering from back pain. Since it was intermittent it took me a while to figure out it was from sewing. Does your chair have wheels? My chair has wheels and when I had carpet I had no problem, since I moved to a new sewing room with wood floors when I sew the motion of stepping down on the foot pedal would push my chair back ever so slowly and minutely that it took me a long time to realize it. I now use a wheel-less chair with the rubber disk mentioned in another post. Now if I can just stop hunching my shoulders......