I have a prescription for physical therapy. I had back surgery and the N.S. says that the numbness should go away months from now. I use the exercise bike for an hour and then Tai Chi and then walking down the hallway back and forth. Nor comfortable going alone outside I have in the past. Need to learn to go up and down stairs. After my first back surgery, my neighbor (no longer living here) walked with me outside and up and down stairs, every day. All one needs is one person, not really a physical threrapist. Must move on to Tai Chi now. I don't like to look at a computer screen.