Adaptations of motor dynamics represent a fundamental mechanism in verbal and non-verbal communication, enabling individuals to coordinate and adjust their behaviors during social interaction. These adaptations depend both on the characteristics of the entrainment signal and on external physical constraints, such as gravity and inertia. However, these external forces are often neglected in existing models of rhythmic coordination, which typically focus on temporal or neural aspects while overlooking biomechanical constraints. The objective of this study is therefore to analyze rhythmic adaptations within an environment that explicitly incorporates gravitational and inertial forces. The presented model is a force controller of muscle dynamics based on sensorimotor learning. Our first set of results demonstrates the capacity of the model to adapt its dynamics to desired velocities. Furthermore, by analyzing the energy expenditure of the system, we show that the model exhibits an asymmetric management of gravity between upward and downward movements which is consistent with observations reported in the literature. Altogether, these findings highlight the relevance and potential of our model for investigating biological movement generation, and in particular, movement rhythms and dynamics adaptations.