Bones have very specific shapes and functions. There is no substitute for drawing from a real skeleton. It is very useful to evolve a visual shorthand of this underlying architecture, as a tool for visualizing movement.
Gesture is the foundation upon which the drawing is built. If the gesture lacks life the drawing will suffer in kind. Learning to spontaneously draw simplified skeletal figures interacting with each other, and the environment, will help you to see “through” the figure, and get a more accurate gesture.
When you get to the point where you can quickly fill a page with these figures, you may find drawing them to be addictive. Play with proportion. Exaggerate, elongate, broaden and flatten. Draw skeletal gestures of basket ball players, trolls and rotund giants. Improvise interactions – maybe add props and an environment. Drawing is about having some control over the marks you make. The more you do it, the better you get.