Just a little bit of a reality check on treadmill running. It is NOT the same thing as running outside, and I don't mean just the fact that when you are running outside you don't have a roof overhead and distractions like TVs.
Even running a flat run on city sidewalks or bike trails, you are constantly having to step up and down over curbs, running up small slopes, on canted surfaces. Even running on a track, you are running around curves.
For most people, exclusive treadmill running translates to flat running this way...if you are running a six-minute per mile pace on the treadmill, your actual time on a flat run outside may be 1/2 minute to 1 minute per mile slower, for an equivalent effort. (This doesn't apply if you only use treadmills occasionally and to most of your running outside).
On a track, add 15 seconds to 20 seconds per mile to your treadmill pace.
In a way, it's similar to the difference between using free weight bench presses (or bar bench presses) and using machines. You can apparently lift far more weight using the machines...but that's because you are not having to expend effort to balance the weights etc.
John the runner :-)