1. Method for determination of the physical and/or psychological state of a subject based on an analysis of a heart rate variability (HRV) of the subject, the method comprising steps of: recording a first set of interbeat intervals of the subject during a first examination time period using a device with a sensor; generating a first frequency distribution of the first set of interbeat intervals in the time domain; investigating the first frequency distribution with regard to a first multimodal distribution to obtain information concerning heart activity; and determining the physical and/or psychological state of the subject based on the information concerning heart activity.