Today I worked out at lunchtime again. I went up to the fitness center and ran 3 miles on the treadmill. I forgot to note my time but it was around 24 minutes.
I start out slow, today at 6.2 MPH for 2-3 minutes, then I worked my way up to 7.4 MPH when I hit 1 mile. I kept gradually increasing the pace 2-3 times per mile and by 1.75 miles I was running 8.5 MPH (7:04 per mile). I even bumped it up to 8.8 MPH (6:49 per mile) for a quarter mile.
Then at 2.5 miles I start gradually decreasing the pace and finish around 7 MPH. I then usually walk another 0.1 mile, depending on if I notice anyone waiting for the treadmill.
I did check my pulse when I finished and it was 180 so I was again running at a hard pace, for me. I have a long ways to go to get to the shape I want to be in, but I've now run 5 days in a row so I'm on my way.