A game apparatus calculates a load value detected by a load controller, and a center-of-gravity position of a player, at predetermined time intervals. Based on the calculated center-of-gravity position, the game apparatus firstly determines whether or not the center of gravity moves, and determines the direction of the movement. Then, the game apparatus determines a change of the load of the player within a predetermined time period. When the amount of increase of the load is equal to or higher than a threshold value, the game apparatus determines that the player swings his/her hip in the direction in which the center of gravity moves.
