You can use a Bluetooth® Smart compatible heart rate sensor, such as the Suunto Smart Sensor, with your Suunto Spartan Ultra to get accurate information about your exercise intensity.
If you use the Suunto Smart Sensor, you also have the added advantage of heart rate memory. The sensor memory function buffers data if the connection to your watch is interrupted, for example, when swimming (no transmission under water).
It also means you can even leave your watch behind after starting a recording. For more information, please refer to the Suunto Smart Sensor User Guide.
Without a heart rate sensor, your Suunto Spartan Ultra provides calorie consumption and recovery time for running activities where speed is used to estimate intensity. However, we recommend using a heart rate sensor to get accurate intensity readings.
Refer to the user guide for Suunto Smart Sensor or other Bluetooth® Smart compatible heart rate sensor for additional information.
See Pairing PODs and sensors for instructions on how to pair an HR sensor with your watch.