There are two practical approaches to producing solid results. The proper approach depends upon the scope of the project. If the project consists of a handful of high-fidelity shots efficiency and economy will be best served through the use of a simple muscle system on mid-ground and foreground characters combine with shape animation work to add visual details into the few shots that require it. If the project consists of a large number of characters and shots that will be seen in high detail the better approach is to build a system that can use simulation and shape animation in pre-production to prepare baked results that can be referenced during shot production and driven by skeletal animation.