Did I mention the fun? That most of the time I am entertained to highly mesmerized like a child who has been granted entrance to the craziest theme park ever? Sure, one gets tired of running, one gets hungry, thirsty and has to pee but it is still so thrilling. (not to mention that it IS what I wanted to do when I grow up) 
btw with us you would not be rewarded for being cocky, believe me... unless you can back it up with work. ^^