Antagonistic muscle force

Hy, I have a question concerning the antagonistic muscle forces. How solves anybody this problem? In the big optimization are there also the antagonistic muscles forces included, or only agonists? Whats about muscles which span over two joints, for example a muscle is in a joint an agonists and in another joint an antagonists. How do you compute this muscle force?

Best regards

the short answer is that we create one big system of equations and take all of this into account. Have a look at the details here: Damsgaard, M et al. Analysis of musculoskeletal systems in the AnyBody Modeling System. Simulation Modelling Practice and Theory., 2006, 14, 1100-1111.
Best regards,