How does the Oura Ring track deep sleep?

The Oura Ring is an advanced piece of wearable technology specifically crafted to monitor sleep patterns, among other health metrics. It closely tracks deep sleep by employing a combination of body temperature sensors, a heart rate monitor, and accelerometers. When one enters deep sleep, the body typically exhibits a stable, lower temperature compared to lighter sleep stages or wakefulness. Likewise, heart rate and variability in heartbeat tend to decrease during deep sleep. The Oura Ring's sensors detect these physiological changes and, through sophisticated algorithms interpreting the data collected throughout the night, estimate the duration and quality of deep sleep. The ring's ability to record minute fluctuations in physiological parameters throughout the sleep cycle enables it to offer precise insights into one's sleep architecture, including the periods of deep restorative sleep.