Szívritmusvariabilitás

Szívritmusvariabilitás, often abbreviated as HRV, refers to the physiological phenomenon of variation in the time interval between consecutive heartbeats. It is not simply a measure of how fast or slow the heart is beating, but rather the subtle fluctuations in the duration of each cardiac cycle. These variations are controlled by the autonomic nervous system (ANS), which consists of the sympathetic and parasympathetic branches. The sympathetic system generally increases heart rate and decreases HRV, while the parasympathetic system slows heart rate and increases HRV.

HRV is a widely studied indicator of autonomic nervous system function and overall health. Higher HRV is generally associated with better physical fitness, resilience to stress, and good cardiovascular health. Conversely, lower HRV can be indicative of stress, fatigue, illness, or an increased risk of certain health conditions. Factors such as age, genetics, lifestyle choices (including diet, exercise, sleep, and stress management), and disease states can all influence HRV levels.

Measurement of HRV typically involves analyzing the electrocardiogram (ECG) signal to determine the precise timing of each R-R interval (the time between successive R-waves on an ECG). Various analytical methods exist, broadly categorized into time-domain and frequency-domain analyses, each providing different insights into the underlying autonomic control. HRV has applications in sports science for monitoring training load and recovery, in clinical settings for assessing patient health and predicting outcomes, and in general wellness for understanding stress levels and promoting healthy habits.