An interface apparatus for modifying the natural pressure distribution of a ski, particularly an alpine ski, along its gliding surface. The apparatus includes a vertically mobile rear sensor on which the rear end of the boot is supported; a rocking device journalled around a transverse axis, the rocking device having an approximately horizontal arm to which the sensor transmits its vertical movements, and a substantially vertical arm; and a linkage assembly connecting the vertical arm of the rocking device to the base of the front binding element, whereby the forces exerted through the sensor are transmitted to the base of the front binding element. The linkage assembly includes a linkage plate, which is rigid when compressed, that is connected to the base of the front binding element by a journal raised with respect to the upper surface of the ski, the length of the linkage plate being substantially equal to the distance between its connection to the base and the vertical arm of the rocking device, so that, in a lowered position, the linkage plate is in support against the vertical arm of the rocking device and transmits to the base the forces of the sensor.