I had gastric sleeve surgery on Jan,21,2014.my start weight was 320 on day of surgery 300.I'm now 280.I don't feel like I'm progressing at all.I walk and walk the treadmill.I have osteoarthritis in both knees however,I still do as much as possible.over an hour walking outside about 20 minutes on treadmill.does anyone have any other suggestions to aide.?