I'm not an aspiring mma fighter, athlete, or anything like that. I just want to get in good shape. I'm too much of a wimp to run, so I've been doing the following for one hour: 1. eliptical 2. stationary bike 3. walking real fast on the treadmill at a steep incline I have no problem with the first two, but I think I get my best workout with #3. The problem is my foot/ankle hurts when I do that, and I limp for about a week because of it. Are there some kind of shoes designed for walking real fast uphill? I've been using running shoes, but they're pretty old. Do I need new running shoes, or are there new walking shoes I could buy? Thanks.