Electrically stimulated muscle is usually modeled using Hammerstein type models, mainly because of the easy later controller design. However, these models suffer from a limitation: they do not include any hysteresis effects which have been reported by several researches. In this paper we present a possibility to include hysteresis in such models. Although significant increase in model accuracy has been achieved, Hammerstein type models remain inadequate to completely describe the behavior of electrically stimulated muscle.