The ski has a box-shaped, substantially rigid middle portion, a front portion and a rear portion which can be easily bent and are elastic and resilient in an upward direction and are capable of torsion in the longitudinal axis. Balancing elements formed of soft, but permanently elastic material, are inserted at the transition of the middle portion to the rear portion in the direction of the rear end of the ski, on the one hand, and/or at the transition of the middle portion to the front portion in the direction of the tip of the ski on the other hand. The balancing elements are inserted in the ski so as to be either not detachable or fixed, but detachable and exchangeable.