The HRM-Pro™, HRM-Swim™, and HRM‍-‍Tri™ heart rate accessories record and store your heart rate data while you are swimming. To view your heart rate data, you can add heart rate data fields (Customizing the Data Screens).

You must start a timed activity on your paired Forerunner device to view stored heart rate data later. During rest intervals when out of the water, the heart rate accessory sends your heart rate data to your Forerunner device. Your Forerunner device automatically downloads stored heart rate data when you save your timed swim activity. Your heart rate accessory must be out of the water, active, and within range of the device (3 m) while data downloads. Your heart rate data can be reviewed in the device history and on your Garmin Connect™ account.

If both wrist-based heart rate and chest heart rate data are available, your device uses the chest heart rate data.