Heart rate variability: for real doctors. Translation from the Russian version of the book, published at Kharkiv, 2010, 131 p.
The basics and practice of the clinical use of the technology of heart rate variability are outlined for doctors of all specialties and students of medical faculties of universities.
8. Regulation in human health
Stress test (bicycle ergometry, treadmill, etc.) leads to a drop in TP power due to VLF and, more, LF components. The power of HF retains, and at higher levels of the load, it may even increase due to modulation (metronization) of respiration.
Recovery of the HRV values after the stress test should take place 10 minutes after its termination. The longer this period is the less adaptability of regulatory systems to physical stress. In healthy individuals, the adaptive capacity of regulation is primarily determined by the characteristics of LF and HF. The degree of their increase directly depends on the level of activation of the high-frequency component that develops during training. The fewer opportunities are for activation of HF and the more significant for HF, the less adaptive capabilities of the heart.
Spectral analysis of HRV is performed at stationary sites (steady-state cardiac contractions with fluctuations around the mean value for a given load) ECG recording and, unlike single samples (lying, sitting, standing), the period of adaptation to stress in a stress test may take longer. By this, the duration of the stress test at each step of the load must be adjusted for the length of the stabilization period.