Abstract: A device for determining and displaying travel data of a user of a sports equipment which has contact with the ground, comprises a first microcontroller associated with the sports equipment for at least recording or partially processing travel data of the sports equipment based on an interaction between the sports equipment and the ground; and a transmitter for transmitting the travel data to a receiver having a display. The receiver has a second microcontroller for at least further processing or displaying the partially processed travel data. The transmitter only transmits within defined transmitting intervals such that between the intervals when the transmitter is not transmitting, the transmitter is switched off. The receiver is synchronized with the such that the receiver is switched on only when the transmitter is expected to transmit and switched off when transmission is not expected from the transmitter.

Abstract: A wheel for roller skates or roller boards, the wheel having a non-rotating axle of rotation and a wheel body rotatable around an axle of rotation, the wheel includes means for measuring the speed at the wheel and means in the wheel for determining its rate of rotation and/or the actual rate of travel of a user of the roller skate or roller board or other sports equipment containing the wheel.