We present a simulation framework for coupled electromechanical simulations of skeletal muscle. Our motivation is to capture the macroscopic muscle behavior while incorporating locally resolved activation dynamics. The simulations are based on OpenDiHu, an open-source, high-performance software framework for neuromuscular modeling. OpenDiHu provides an electrophysiological solver capable of computing the action-potential propagation along muscle fibers, including cellular dynamics models such as the Shorten model. Then we couple the electrophysiology solver to a continuum mechanics solver via a muscle activation parameter, as proposed by Heidlauf et al. In addition, to account for neural feedback mechanisms relevant to muscle function, the framework is extended by coupling the electromechanical muscle model to a motoneuron pool and a muscle spindle model. We use our framework to simulate the agonist–antagonist myoneural interface. This clinically motivated use case requires the incorporation of a second muscle and introduces additional coupling challenges, as the paired muscles are coupled both via a tendon and via the disynaptic reflex pathways. To address limitations of OpenDiHu’s native coupling capabilities, we employ the coupling library preCICE, which also enables the replacement of OpenDiHu’s finite element solver with established tools such as LS-DYNA or FEBio.