Abstract: The invention relates to a device for monitoring the physical fitness using a pulse watch part (1) for detecting heart pulse rate data and an evaluation apparatus for providing fitness information which can be displayed by means of a display device and for whose derivation a processing unit (16) is present which is designed for reading in and including personal supplementary data. The accuracy of the fitness information made available is favoured by the fact that the personal supplementary data comprises physiological additional data, for whose detection additional equipment with an additional measuring apparatus (2) is provided, which can be connected, in terms of data transfer, to the pulse watch part (1) directly or indirectly for the automatic transmission of the physiological additional data and/or heart pulse rate data.