Did a run at the high school track this evening. Surface is flatter and has that newer spongy track surface. Have been getting a little bit of knee pain, something I have never in my life had, so I am hoping this will help. Did significantly better than my last run at this distance. Still had to walk a bit though. See the dips in speed and you can tell when I was walking (6 times). Regardless, I am very happy with the improvement. Over 4 minutes faster!