…and it is probably going that you've no idea what Meaning or have needed to glance it up and even now never recognize what this means. Heart Rate Variability (HRV). HRV expresses the purely natural variation of IBI values from conquer to defeat. HRV is carefully connected to emotional arousal: https://8wonder.xyz/hrv-training-how-to-use-your-hrv-for-training-control/