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.
Keep in mind that Oura doesn’t track heart rate during exercise or other activities during the day. The only exception to this is the use of Moment, which allows you to meditate or check in with your body. Certain Moment sessions, upon completion, show you a snapshot of your resting heart rate during the day.
To learn more about HRV, visit The Pulse.