Before you can build something, you have to clear away some of the existing stuff.
For instance, poses. Poses are ways to position the body and rearrange extremities into a meaningful configuration. In short, it is a kind of sign language, separate from spoken or even written language.
Just as beginning artists have preconceptions about the world and draw what they know instead of what they see, drawing stock poses, based on popular art is a guarantee for dead art. Let different people do the same strong pose, and see how they slightly differ from each other. Different people do the same thing differently. So should your characters.
You can’t assume that once you’ve understood a certain pose, you can just put that same pose on every character. It has to fit the configuration (the build, physique) and the personality (how they behave) of that particular character.
To construct you have to deconstruct first, unlearn some of what you have learned.
That is all.