I want...

...amazingly healthy arm and hand muscles.

I want my muscles to...
relax easily
do sustained bouts of playing
repair itself easily
move fluidly
ideally not to hurt!

Things that can help with this:
good food
rest
good posture
exercise that counters the oddness of doing one thing so much
good exercise (fluid) *** think this is really important and needs to be explored more

There are more or more subtle / specific distinctions to be made here... this is to be added too.