Your heart doesn't beat at a perfectly steady rhythm. Heart rate variability measures the gaps between beats, and a wider variation signals better stress recovery and nervous system health. A narrower variation can indicate stress or overtraining.
Heart rate variability, or hrv, is the variation in time intervals between heartbeats. If you have 60 beats a minute, that doesn't mean that your heart beats once every second. It means that it's beat 60 times in a minute. But the variation between those beats could be anywhere from partial second to more than a second to two seconds. Unlike your heart rate, which measures the number of beats per minute, HRV looks at the precise intervals between each beat. So a higher HRV indicates a well functioning, adaptable automatic autonomic nervous system, while a low HRV can be a sign of stress, fatigue, or other health issues. So HRV is a powerful indicator of your body's autonomic nervous system involuntary functions like heart rate, digestion, and your respiratory.
