Ok I am 15 years old and have a very poor level of fitness. I went out this morning and for some stupid reason decided to be all competitive and tried to run a mile in around 7 minutes was my target. Predictably it actually took me 12 minutes to finish the mile and i was shattered and had sore feet. I understand i will just be told run the mile at a very very slow pace next time even though you will end up finishing in like 18 minutes. But i struggle to understand how running it slower will make me quicker?