The changes of heart rate variability indices reactivity in response to controlled breathing during the general endurance training

Abstract

The aim: to determine the changes in heart rate variability (HRV) indices during spontaneous and controlled breathing of qualified athletes who were engaged in physical activity aimed at endurance development for a long period of time. Materials and Methods. We examined 28 highly qualified male athletes aged 20.2 ± 0.7, who were engaged in various sports. 30 trainings with the focus on the general endurance development were conducted during 7 weeks. Parameters of HRV during spontaneous breathing (SB) and controlled breathing 6 (CB6) and controlled breathing 15 (CB15) times per minute were surveyed. A medical examination of athletes took place in the morning hours, fasting and using spiroarteriocardiorythmography (SACR). Results: The changes in HRV during controlled breathing were caused by respiratory frequency and rhythm. However, reaction of the HRV indices was significantly different and showed, as a rule, the possibility of appropriate regulatory mechanisms initiation. Heart rate variability indices did not differ from each other before and after training during CB6. The increase in endurance was displayed in response of HF (ms2) – HRV that SB was not practically influenced by controlled breathing. That differed them from the data at the beginning of training where there was significant decrease in HF (ms2) to 967.2 (479.6; 2540.2) during CB15 in comparison with SB (2035.7 (75.3; 6037.3)) and CB6 (2560.9 (1361.6; 5098.0)) (P < 0.05). There was significant decrease in LF/HF (р < 0.01) during CB15 in response to increase in endurance. Conclusions. The use of CB tests in athletes who developed their endurance allowed us to determine that an increase in the latter was reflected in the HRV indices reaction on CB15, which was characterized by pronounced increase in HF and decrease in LF/HF. During CB6, the peculiarities of the HRV indices reaction in case of endurance increasing have not been found.

Keywords

• breathing
• heart rate
• athletes
• physical endurance