Exercise and Fitness

My philosophy of exercise is to do what you love. It's admirable that you're working on 8 minute miles, I think you're right in inching up toward it a little at a time.
For me, treadmills are pure torture. I need the variability of terrain, my body can't take the same stressing in the same places over and over. Shortly after I bought my treadmill, I got a stress fracture in my foot. Since then I seldom use it, except for periods of prolonged nasty weather.
I love to get out in the fresh air, but then I live in an area where I have great parks to choose from. It's funny how 20 degrees seems so darn cold when you start running and so darn hot when you finish.