My knees are pretty shot. I do almost all of my workout at 10deg on a treadmill. I stop every 2 miles and do a short little round on a bowflex. At my current pace, I should shed about 20lbs this month and be close to 180. Based on what I have seen from others, I should then load up one of my old packs with 45#(that is about what my 10 day pack weighs in at), and get after it some more. I think strengthening my legs with relatively low impact has helped pull my knees together and made down hills much easier on me. I think a good goal for me by july/Aug would be 8 miles in a day with a (med)pack on and not be burned out and sore the next day. This is all a little new to me in the last few years. Getting old and sitting at a desk everyday really takes a toll.
If I bump the speed above 3, I start getting the lungs burning a little. I assume this is what I should be doing to help train for high altitude?? I am at a whopping 350ft EL in the Willamette Valley.