Changed up my treadmill time yesterday morning.
After a warm up walk (bout 3 or 4 minutes), I ran @ 7mph for 1 min, then walked @ 4mph for 1 to 1.5 min (it varied each time). Alternated for about 20 minutes, ran the last bit of time at 8mph to get 2 miles in before hit 25 minutes (it was 24.4).
I like short times of actual running, compared to longer times of jogging. It feels better. Not sure if I could it longer than 20 minutes or not. Total time on the treadmill ended up being about half an hour by the time the cool down walk was done.
Also didn't realize how many muscles in your legs are used when you run.