From Heart Rate To “Stand Up”: How Do Wearables Turn Body Data Into Health Advice?

Oura filed for a US IPO this week, planning to list its shares on Nasdaq under the name OURA, according to Reuters. The company makes smart rings that track things like heart rate, sleep and physical activity, then turns that information into scores for things such as readiness and recovery. Oura isn’t alone; WHOOP, Apple, Garmin and other wearables can also take measurements from your body and turn them into scores for sleep, stress, activity and more.

You put on a ring or watch, go about your day, and eventually your device tells you that you slept badly, need more recovery or should probably take it a little easier. But how does a bunch of data measurements become a recommendation about what you should actually do?