Heart and Fist

It's a funny thing that your heart is shaped like your fist.
Hearts break all the time but how often do fists break?
Bigger fists can hurt more but does that mean that bigger hearts hurt more?
I think so.
Hearts get tired and they get old but does a fist ever?
A clenched heart hurts you but a clenched fist hurts someone else.
And both pains are unbearable.