I can say this, when running or doing anything physically strenuous you will learn a lot about yourself. In training for hockey we used to have to run upwards of 10 miles. After the first 3 it is all mental. So many times I just said quit, stop, walk but I wouldn't. You can keep going you just have to tell yourself you can. I tell you after fighting your body with your mind and winning. That is euphoria.
