How to continuously record heart rate on Apple Watch

By default, Apple Watch measures your heart rate once every few minutes. If you need denser heart rate data that's recorded continuously, here's how to do it.

One warning: this will drain battery faster since the heart rate sensor and processor will be on continuously. So you may need to recharge your watch.

To record heart rate continuously, follow these steps:

1. Open the Empirical Health app on your Apple Watch (pictured above)
2. Below the heart rate chart, press the "start recording" button.
3. Heart rate will be recorded continuously. The chart will update with your latest heart rate data, and the timestamp will tell you how recent the reading was (e.g., "2 secs ago").