. . . "Here, by regarding when the weight ratio WR is 1.0, that is, when the body weight value (reference value) and the current load value match with each other as a reference, the upper side of the graph is a side where the load of the player detected by the load controller 36 is added, and on the lower side of the graph is a side where the load of the player detected by the load controller 36 is reduc" .