The Oura app (v. 2.0 and later) shows your lowest resting heart rate and average heart rate variability (HRV) readings every day. You can also see both measures in detailed graphs which illustrate how your night-time resting heart rate and heart rate variability vary throughout the night. The graphs are based on 5-minute averages. You’ll find the graphs in the Oura app’s Sleep and Readiness sections.
What can I learn from the graphs?
Tracking how your resting heart rate changes throughout the night helps you understand how your body and mind recover from daily strain. You can learn more about tracking your resting heart rate curves in the Heart rate while sleeping article.
Heart rate variability is a good indicator of especially cardiovascular, but also overall health and general fitness. Your HRV can react to changes in your body even earlier than resting heart rate, so keeping an eye on your own HRV baseline and trends can provide useful insights into your recovery and wellbeing.
To learn more about heart rate, check out the What is heart rate variability and what you can learn from it and How to measure heart rate variability articles.
There are gaps in my graphs, why?
Sometimes there can be gaps in the night-time resting heart rate and/or heart rate variability graphs. This usually means that something has interfered with the pulse signal, and the ring hasn't been able to detect your heart rate.
Pulse signal tracking may be disrupted if the ring sits too loosely on your finger, and the ring sensors don’t have a good quality contact with your skin. The ring should sit comfortably but snugly enough, and the sensor bumps should be underneath your finger. You’ll find more information about wearing the ring in ring sizing FAQ. If the ring feels too loose at bedtime, try wearing the ring on a different finger or if kept in same finger, just before bedtime ensure the LED sensors are under your finger and slide it towards your knuckle for better snugness (to thicker part of your finger).
Body signal tracking can also be temporarily disturbed if the ring detects a lot of movement, or if you sleep in a position where your hand goes numb (partially blocked circulation).
There are situations where Oura may not show your resting heart rate and heart rate variability graphs properly, for example if your resting heart rate is exceptionally low (below 30 bpm) or you have exceptionally high HRV (respiratory sinus arrhythmia, or other arrhythmia).