Imagine the worst pain you have ever felt. The kind that sucks the breath from your lungs before you can catch it. Every step is excruciating. You can't even shed a tear because it would take energy and oxygen to do that, and right now, all of your strength is going towards simply putting one foot in front of the other as fast as possible. Your numb run turns to a limping jog. Screw the mile repeats and fartleks you did to train for this exact moment. Forget about the Wednesday night track practices and the nights meticulously writing down your lap times. The race is over. Right now, you run only because you know that will end your suffering faster. Now imagine doing this in 45 degree air, 54 degree water, and 30 mile an hour wind gusts. Imagine doing this at Triathlon nationals: the sub 3 hour time slot you spent the last 5 months preparing for. You picked up a part time job, iced, heated, foam rolled, stick'd, therapied, begged, pleaded, braced, wrapped, bio freezed, rock tap...
I like geography best because mountains & rivers know the secret: Pay no attention to boundaries.