Based on two studies where people sat upright without a backrest and attempted to keep a natural posture, or performed a typing task. The conclusion was that the outer stabilizing muscles are less active when sitting on the Backapp. Lumbar flexion was significantly reduced and so was the activity of one of the main lumbar muscles. The conclusion was that sitting upright on the Backapp is easier than sitting upright on an ordinary office chair. You are able to sit upright for longer without a back rest while using the Backapp.