The analysis of heart rate (HR) and heart rate variability (HRV) is a well established concept in sports science and occupational medical research. In the course of this research, the development of the HRV was documented over a period of seven days after intensive athletic endurance (semi-marathon run). This study aimed to elucidate, a possible relationship between morning heart rate variability during the medium-term recovery phase and the physical fitness within a group of leisure-time ath-letes Moreover, the data should also provide more detailed information about the possible duration and extent of possible vegetative changes during the regeneration phase after long-term en-durance. This article presents the results of a 23 participants sample with an average age of 32-7 ± 7-9 years, who completed a semi-marathon competition (21.1 km) as part of a running event. During the competition, the heart rate was recorded individually (NN intervals) with the help of a mobile measuring system (Polar RS800CX®). After the competition, a morning 10-minute resting period was carried out for 7 days. The recorded NN data were obtained with the software Kubios HRV® Version 2.0. Based on the maximum power of a previously performed Spiroergometrie performance diagnosis, two power groups were defined by means of median split (S1 Pmax < 300 watt n-11 and S2 Pmax > 300 watt, n = 12) and compared with different HRV measurements. The results of the HR measurement showed values of 55.2±4 4min-1 to max 58.7 ±5.6 min1 and for group S2 51.0 ±7.9 min1 to max. 55.1 ±4.7 min1 Concerning the evaluation of HRV parameters, namely the time and frequency range, a shift of the vegetative equilibrium towards a raised sympathetic tone was shown for both groups. During at the beginning of the regeneration phase, the variability in the sympathetic and vagal influenced LF band was strongly pronounced and a progressive reduction of the LF variability was observed in the further course. The resultinq ratio of low- and high-frequency HRV (LF/ HF), an indicator of the sympatho-vagal balance, was most pronounced comparing the second and fifth day of the regeneration phase (3.05 ± 1.37 vs. 1.47 ± 0.76, p< 0.001) for the total group. By means of a two-factorial variance analysis, carried out with measurement repeat, no group-specific differences could be detected (p > 0.05). In conclusion, these results are in favour of the thesis, that exhaustive exertion leads to a multiple-day, sympathetic-dominated control of the cardiovascular system, which is not necessarily visible, when HR is exclusively monitored. This process was demonstrated within the whole study population, regardless of their previous ergom-eter performance thus, adapted HRV monitoring could make a valuable contribution to the planning of an individually adapted regeneration process.
© Copyright 2018 Herzfrequenzvariabilität: Methoden und Anwendungen in der Sportwissenschaft, Arbeits- und Intensivmedizin sowie Kardiologie. 7. Internationales HRV-Symposium am 4. März 2017 in Halle (Saale). Veröffentlicht von Feldhaus, Ed. Czwalina. Alle Rechte vorbehalten.