A game apparatus includes a CPU, and the CPU judges a motion of a player on the basis of a cycle of a load value input from a load controller, and selectively displays an animation of a player object according to the motion in a case that the motion by the player is a large-flapping motion, the CPU changes an updating velocity of an animation frame according to an arm-raising motion and arm-lowering motion of the large flapping motion. On the other hand, in a case that the motion by the player is a small-flapping motion, the CPU changes the updating velocity of the animation frame according to only the arm-lowering motion of the small-flapping motion. Thus, the motion of the player and the animation are synchronized.