Must be and I even plan to get some HIIT in pre workout today since all I have to do is jump my backyard fence to get to the track.
Ankle and leg felt good but my ankle popped and cracked during my warm up but it was a good pop and crackle because it seemed to free me up some. That's another thing is my whole body just seems freer and more mobile than it has. I'm sure its from the running to because last year (2012) I was more flexible/mobile when I was doing cardio in the AM and PM.
So since its about to get cold and possible wet around here I'll be grabbing my treadmill and using that in the am/pm 4-7 times a week.