You are probably pushing yourself too hard, become demotivated and quit. Think about it this way: you are never going to beat Usain Bolt no matter how hard you

You are probably pushing yourself too hard, become demotivated and quit. Think about it this way: you are never going to beat Usain Bolt no matter how hard you try. So just go for small improvements. Run half a mile, limp another half, go home. Repeat this 3 times weekly for a month. By the end of the month you'll be running that whole mile. Now keep it up and get to 2!