An arrangement, a communication module, a sensor unit and a method for monitoring physical performance includes at least one communication module having means for providing an output DC power by wire, and means for receiving at least one sensor signal representative of measured physiologic activity from at least one sensor unit. Said at least one sensor unit adapted to measure physiologic activity and to generate analog measurement signals in response thereof and is connected to said DC power wire and having means for processing and sending a sensor signal representative of measured physiologic activity by a wire to said communication module. A processing unit is adapted to form from said analog measurement signals data messages in predetermined transmission time slots. A wireless communication unit is used for transmitting the data messages at successive time slots using a wireless communication protocol to a wireless receiver device.