LtH posted the other day about mistakes runners make and one of mine is running a mediocre run every time and not switching it up.  So today I did some speed work.  I did fartleks and I tried to stay around 10min mile pace (that is fast for me ) during my fast parts.  I ended up doing very well but in my brain 10 minute mile is hard so everytime I looked down at my watch, I was running like an 8 minute mile.  My goal is to be able to work on maintaining a 10 minute mile pace during that time.