Treadmill Mile Repeats

I hit the treadmill for a 3x1 mile workout a few days ago. I referenced this table for what mile/hour equals what mile pace (which was the same link I used for my treadmill 5K recently), and I figured I'd be between these speeds:

Maybe starting around 10.6 mph and finishing around 11.4 mph.

After a 1.5 mile WU and about 0.2 miles of walking rest, I sped up for the first interval. I started at 10.6 mph and bumped it up to 10.8 mph by the end of the first mile. Mile 1 was 2:50.2 + 2:47.4 = 5:37.6.

I started mile 2 after 0.2 walking rest again (well really only about 0.13 walking rest before cranking it up because the treadmill takes a while to get up to speed), and I started at 10.9 mph. I bumped it up to 11.0 before a half mile, and ended the last 90 sec or so at 11.1 mph. Mile 2 was 2:45.4 + 2:43.1 = 5:28.5.

Starting mile 3 was intimidating because I started at 11.3 mph. Again, around a 1/2 mile in I bumped it up to 11.4, and then up to 11.5 before too long. I was worried about dying at the middle of this workout, but I finished it feeling OK - there's less of a "sprint to the finish" when running on a treadmill. Mile 3 was 2:41.1 + 2:37.8 = 5:18.9.

Red splits were the intervals, with 2:41 and 2:37 walking between.


Data. Nothing unexpected. (Notice there are more "idle" times as I go on -
I was more inclined to hop off the treadmill after my mile later in the workout.


Heart rate with some obvious climbs.


Graphs showing my speed as I stopped to walk before cooling down.

Between this workout and my treadmill 5K a few weeks back, I think I have my baseline for winter speedwork. I want to try to stay on top of speed this winter... and try to do it OUTDOORS when it's not too icy!