1. A method of numerically simulating muscle movements along bones and around joints comprising: receiving, in a computer system having an application module configured for performing time-marching muscle movements simulation installed thereon, a computerized model containing a plurality of truss elements and at least one roller, said plurality of truss elements being configured to represent a muscle strand while each roller being configured to represent a joint and said plurality of truss elements being associated with a muscle bio-mechanical property model; conducting the time-marching simulation using the computerized model with the application module in the computer system, the time-marching simulation containing a series of consecutive solution cycles representing passage of time; calculating axial stresses and strains of said plurality of truss elements at each solution cycle; and applying slipping and swapping adjustments to each truss element pair that straddles each roller to obtain numerically simulated movements of the muscle strand along bones and around joints.