You can automatically connect to Bluetooth-enabled accessories to add cadence and power metrics to your cycling workout view. You can also view estimates of your functional threshold power—the highest level of intensity you can maintain for an hour.
When you start a cycling workout, it automatically shows up as a Live Activity on your iPhone. Tap it, and it will take over the entire display, making it easier to see your metrics while on a ride.
Tap Bluetooth, then below Health Devices, tap the sensor you want to connect.
Below Set Up Device, tap on your Apple Watch.
Go to Workout > Cycling Power.
Tap Custom, then enter an FTP.
When you enter an FTP, your power zones will be automatically recalculated using the same percentages.
Tap 6 Zones below Power Zones, then choose the total number of Power Zones.
Tap a zone to enter lower and upper limits.
You can also open the Apple Watch app on your iPhone, tap My Watch, go to Workout > Cycling Power, tap Custom, enter an FTP, change the total number of Power Zones, then tap a zone to enter lower and upper limits.