Frogs use jumping as their primary mode of locomotion, but the force required for powerful jumps cannot be explained by leg muscles alone. In this study, we focused on Rana tagoi, a species capable of high vertical jumps, and investigated the interaction between leg kicking and trunk snap-through buckling. A musculoskeletal model was developed using MuJoCo, with muscle dynamics based on Hill-type models and anatomical parameters measured from actual specimens. Simulations showed that the model achieved high vertical jumps when both leg and trunk mechanisms were activated simultaneously, supporting previous results from frog cyborg experiments. These findings suggest that coordination between leg propulsion and trunk snap-through buckling is critical for vertical jumping. Future work will refine the model using detailed 3D bone geometry and quantify the role of elastic energy in jump performance.