At Suunto we use advanced sensors and algorithms to generate metrics that can help you in your activities and adventures. We strive to be as accurate as possible. However, none of the data our products and services collect is perfectly reliable, nor are the metrics they generate absolutely precise. Calories, heart rate, location, movement detection, shot recognition, physical stress indicators and other measurements may not match the real world. Suunto products and services are intended for recreational use only and are not meant for medical purposes of any kind.