HEART RATE VARIABILITY: OBSERVATIONS ON ITS APPLICATION IN THE ANALYSIS OF LOAD AND PERFORMANCE IN FOOTBALL
Introduction: During the last few years the use of the variability in heart rate (HRV) applied to sports has increased considerably, showing that is of great interest. Method of analysis: Different methods of measurement exist of which include the method 5’-5’, the analysis during short periods of time (1-10 minutes) and the study of said variable during the night, that is to say during a long period of time (various hours) or during the first slow wave sleep phase (SWS). Interpretation of the variability of heart rate: HRV seems to be a very useful indicator in the analysis of fatigue after exertion. This is due to the replacement of metabolites, and other recuperation processes which are determined by the Automatic Nervous System (ANS). After exertion, depending on its intensity, the values of HRV are altered, and are then restored during a period of 24 to 72 hrs. HRV can also be modified due to pre competitive stress. On the other hand, progress in aerobic capacity through the use of training loads, which are well tolerated by athletes, can increase HRV. However, if maximum loads are used the effect is the opposite. HRV in football: It has been demonstrated that in football HRV can diminish after a match. In addition, performance has been linked to changes in HRV and in the coefficient of variation (CV) of said index. Conclusions: HRV appears to have a great potential in the study of changes in physical loads, as does the capacity of athletes to assimilate this.
heart rate variability, football, performance, fatigue.