Optimal human arm trajectory formation was investigated on the basis of physiological characteristics of skeletal muscles and dynamic properties of contracting muscles, and a minimal effort criterion prescribed by isometric muscle contraction was proposed. The dynamic properties of contracting muscles were discussed and the dynamics of human arm was modeled. The arm point-to-point movement problem was converted to an optimal control problem by using the proposed criterion. According to optimal control theory, the iterative algorithm used to obtain the optimal trajectory was designed. The control laws and the time history of human arm movement were found. The results of numerical simulation indicate that the proposed criterion for the prediction of optimal arm movement trajectories is effective.