What is Heart Rate Variability?
Heart rate variability (HRV) is the constant variation in milliseconds between your heartbeats. The HRV value provided by Oura can range from anywhere below 20 to over 100. HRV differs for everyone, so be sure to compare changes in your HRV to your baseline and not others.
Oura calculates your nighttime HRV from the rMSSD, a well-known HRV parameter that provides a reliable view on your Autonomic Nervous Systems' activity. The HRV you see on the Readiness tab is the average of all the 5-minute samples measured while you sleep.
To learn more about HRV, visit The Pulse.