Very interesting. Thanks!

I actually think that it would still use energy even if you could "lock" your skeleton in place, simply because there would still be a gravitational force acting on all of the atoms in your skeleton that would need to be counteracted. This sort of builds on what gim said above about the electrostatic repulsion in atoms balancing out the force of gravity on Earth, and I probably should have phrased my question better originally to tease out this issue. Essentially, my question is what is happening to that electrostatic energy that is keeping the Earth from collapsing? Is it being used up? Even if the two forces are roughly in balance, and there isn't any dramatic motion, surely there is some give and take between gravity and the electrostatic force on the atomic level. If so, then the electrostatic force really would be moving things against an opposing force, and that movement surely uses up energy. Right?

I've always been confused about how energy and gravity interact. Specifically- "why isn't a table using energy?" If I were to hold a dumbbell with my elbow at a 90 degree angle, it would take energy for me to keep gravity from pulling it down. However, I can place a dumbbell on a table and it could sit there for centuries. Is it using any energy to keep the dumbbell from falling down?