Survey perspective on the indices of HRV and HRR: analysis of a case study in the men's artistic gymnastics.

The Heart Rate Variability (HRV) is an index on the heart rate variability, its measurement is assuming great importance as it can be deduced from these findings is a lot of information, for example, assess the risk of cardiac arrhythmias and heart failure, identify of the balance between sympathetic and parasympathetic nervous system, formulate on OTS predictions or perform screening of deepening cross on specific clinical cases and more. The Heart Rate Recovery (HRR) is an index of the rate of heart rate recovery. The action potential for a heart cell can be divided into five stages: 0 (rapid depolarization), 1 (partial repolarization), 2 (plateau), 3 (repolarization) and 4 (pacemaker). From the heart can be recorded two main types of action potentials: the rapid response that is recorded in the fibers of the atrial and ventricular myocardium of the specialized conduction fibers (Purkinje fibers) and the other type, the slow response was recorded from the sinoatrial node , the natural pacemaker of the heart and the atrioventricular node. The variability of the heart rate is usually evaluated according to two main processes: in the time domain or in the frequency domain: in the time domain is done using two basic types of indices: those that take into account the duration of the individual RR intervals. All the variables of the time domain, reflect predominantly vagal tone. In the frequency domain is carried out with the spectral analysis, a method that allows, with various mathematical approaches to build the frequency spectrum of the phenomenon. From the ECG trace is passed to tachogram (trend of RR intervals) and from this to the power spectrum. In the frequency spectrum components can be identified: high-frequency (HF) index system PNS, low-frequency (LF) index SNS system, a very low frequency (VLF) to ultra low frequency (ULF).