The HRV as a Therapy Prognosis Method Until recently the determination of the Heart Rate Variability (HRV) was an insignificant method in Central Europe. In a number of other countries, it indisputably belongs to conventional medicine, while in Germany even many cardiologists do not do much with it. At most it is used as an additional program for the evaluation of the 24-hour ECG. Its most widespread application is found in sports medicine, where in this respect it also appears that the Polar sports clock [...]