So, this happened.
What's the trick this time?
Train with someone with a better pace than you. My running partner runs at 6'45 and my best record was 7'10 (comfort zone at 7'30, lazy mode at 7'45).
So when we run together, I pushed my self to stay at my best, and even better! At the end of the run, I could not believe myself that I can manage to run in that pace all 17K through.
PS: I lost one toe nail.