Do a thing once or twice and you gain confidence, but do it every week, and you earn confidence.
I ran 6 miles from the RAC to my home on Monday night. 6 miles in 1:16:48. Faster than a 13 minute pace. It was dark by the time I navigated the streets into my subdivision, and it felt really good to be out there. My heart rate stayed in the 132-155 zone all but 5 minutes of the run, which means I’m sure I could push it and make my 10k target time of 1:18:13. In a burst of optimism near the end of the 6 miles, I started fantasizing and doing math and realized that if I could run 0.2 miles more in the same time I would have done the race in exactly twice my 5k speed, or 1:16:48.
Well, maybe if I do it once.