I do love the fact that I actually train and don't just go out for a daily run. Just running the same thing day in and day out can get very, very boring. That type of the same routine each and every day is probably why so much of America is over weight, it's hard to start and then it can get very boring and once you don't do it one day it gets easy to not do it the next day.
Anyway back to my point, when you actually train for someone there are two advantages. First, the fact that each run is different, could be a distance run, a recovery run, a speed run or tempo work. Second the achievement from accomplishing your goal, like a 5 K or a 10 K or a 1/2 marathon at the end of it all, and then you start all over and work to do better the next time.
Today was tempo day, so 5 minute warm-up run, then 400 meters (sprint basically), then 2 minute and 15 seconds recovery jog and repeat 9 times, then the 5 minute cool down. It's probably the "easiest" day even though the 9 times of sprinting 400 meters can become quite difficult, but this run goes by faster then any other one, even though it takes 46 minutes with all the recovery jogs and 5 minute warm-up and cool down. I recommend trying it.