HEART RATE VARIABILITY AS THE ADAPTATION RESERVE INDICATOR OF CARDIOVASCULAR SYSTEM

Abstract

Background: The efectiveness of the vegetative regulation action might be controlled by the method of heart rate variability (HRV), which has been very popularly used over the last 10 years worldwide. The analysis of many clinical studies indicates that the severity of the disease might be controlled using the method of HRV.Material and methods: All the experimental and controlled group participants, which consisted of healthy students with none sports experience, underwent the examination according to the 5-minute standard protocol of HRV. In addition, all the examinees performed a bicycle stress test. After the bicycle stress test, some additional tests of HRV were also carried out.Results: It was found that some signifcant diferences, between the group of sportsmen and the group of patients, exist. The parasympathetic activity of LF is maximum in athletes and tends to decrease in patients with cardiovascular pathologies. The decreases of the activity of the vasomotor centre was noticed in both study groups. The sympathetic system activity was the lowest in athletes.Conclusions: At the high depression of the vegetative regulation, any signifcant load (physical or psycho-emotional) indicates cardiovascular instability which remains beyond the capacity of adaptation. The higher the variability, the more stable the CVS is to the external loads. A sharp decrease of the variability, such as the heart vegetative innervations, causes deteriorating quality of the regulatory mechanisms and, as a result, the risk of cardiovascular diseases increases.Keywords: heart rate variability, deterministic and stochastic loads, cardiovascular system