I CAN'T Do Anything Humanly Possible

I have no hopes of becoming an olympic medalist.  My genetics limit my ability to win the javelin throw.  I simply cannot throw a javelin far enough to win a gold medal in this olympic event (especially in my current condition).  I would get smoked if I even entered this event.  I often say I can do anything humanly possible.  I'm exceptionally confident, but I'm also realistic.  When I say "I can do anything humanly possible," that means I just give myself more credit than most people.  I laugh to myself when I hear a person say he or she can't do something when he or she just has an extremely difficult time doing that thing.