Part two of my two-a-day

Well, I was warmed up and ready to test out just how fast I could move over 4k. I jumped on it early, running hard and determined. I was 3:48 for the first km. Second one was a little up hill and I backed off some as I was trying to save something for later, so it was a 4:14. Next one leveled out but I kept pushing but starting to feel the fatigue in 4:08. Final one was real hard, knowing where I would finish but not trying to look. My heartrate was up over 175 and I had almost nothing left. I clocked in at 3:48 again. Holy shit. I ran 4k in less than 16 minutes. Whoot whoot for me. 15:59 ~ 4km, 3:59 per km.