I started running after my retirement in Sept 2011. I had been a Family Physician in Canada and the US for 40 years. I was in poor physical condition and I needed 6 months to feel comfortable in the gym. Last summer, I started training to run my first 5K. Eventually, I ran 3 of them . However in January 2013 I stared with left knee pain. This was felt along the medial and inferior aspects of the patella. I went to PT for 8 weeks with very little improvement. I picked up the "The Cool Impossible" and after reading this, I already know how I was running improperly-Forefoot strike but no heel drop and there there was always tension on my quadriceps muscles and eventually patella-femoral syndrome. I will start slowly with the foot strengthening exercises as well as changing my form while running. Also I will not use the treadmill as I can see how this would change your form.