If you own a heart rate sensor supported by Bluetooth technology you can connect it when you use the mobile app.
This video will show you how to connect to a heart rate sensor.
You can connect your heart rate sensor before you start your workout by tapping "connect" in the bottom navigation bar. You can also connect your device after you start your workout by tapping the Bluetooth icon at the bottom of the workout screen.
When you tap the Bluetooth icon the app automatically starts searching for available devices and lists them on the screen. To make sure you can easily tell all your devices apart, the app uses a heart icon for all heart rate devices and a bike icon for power meters and cadence sensors.
If your chosen device isn't listed, please check that it's open for connectivity and not already connected to another device, then tap "rescan" at the top of your screen. If your device still doesn't appear on the list, try to restart the app and search again.
To use Bluetooth connectivity BLUETOOTH must be activated on your smartphone. For some versions of Android, you also need to activate LOCATION in order for Bluetooth to work.
Tap connect on the device or devices you want to use. Then tap "continue".
When connected to a device, your performance data is shown below the circular timer at the bottom of the screen. The current target interval intensity is shown in the lower part of the circular timer itself (see example below). Learn how to "favorite" a device, or how to adjust your HRmax or FTP during the ride. You can also learn how to flip back and forth between viewing your percentage output or raw performance data.