The best rigging systems we have so far are very expensive MoCaps for Hollywood movies.
I'll let you decide how great MoCap is at moving muscles,tendons etc etc like real Humans.
No Riggs will move mucles,tendons etc etc like real Humans.

I suppose it would be possible to apply a MoCap animation to a Maya rig that included a muscles system, but even that would provide only an approximation of the real. The human body will produce unique surface deformations that vary with position as well as muscle tension. To make things worse, the deformations vary from person to person and defy any "one size fits all" parameter. Perhaps a system could be devised for custom positional morphs, but the changes wrought by muscle pressure are myriad and daunting

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