Go to Alan Fraser's Craft of Piano website and try this exercise invented by Franz Liszt: Bicycle Spokes Exercise.
The exercise is didactic in purpose. When you play, you aren't going to leave your fingers immobile and you aren't going to activate them solely by moving your forearm. The intention here is to illustrate the solidity of playing on your skeleton by lining up the bones.
Give it a try,and if it helps you, I recommend Alan's books. (This is an unsolicited endorsement.)
The proof lies in how it works for you. For inspiration, check out Horowitz playing Scriabin in his concert in Moscow. Bless his heart, he's 83 and when he stands he's feeble. Not so, sitting at the piano! Formidable hand structure with skeletal alignment affords him the power to break strings were he to unleash it fully.