I'll tell all of you another point you are really missing out on with treadmills. Pat Porter would travel about 20 miles outside of Alamosa to run a 12 mile hill/mountain run every week to 10 days. I would guess the incline was in the 5-6% range. How many of you have a 6 mile long hill at 6% you can run?
All you have to do is jump on a treadmill. I guarantee it will help your training. Just make sure you cut your intended pace by 1:30-1:50/mile.
If you aren't using the incline on your runs, you are really missing out on a great opportunity. A big advantage is that your legs get a rest from the pounding even though you can be maximizing your effort.
I ran a 16 mile race a couple years ago that had rolling hills the first 12.5 miles and then a mile long hill at 12% incline. How would you ever prepare for something like that?
I got the elevation profile of the course and figured out the elevations of the climbs. I made a chart of how long I had to run at that incline and then figured out how far a recovery I needed at level. I figured the pace of the recovery so my average mile pace was equal to the goal I thought I could run the race in. I compared previous years results with what some of them ran on flat races.
I caught the leader right after the mile long hill and finished 5 seconds under my goal time even though I had never been there before.