Your device analyzes your heart rate variability, stress level, sleep quality, and activity data to determine your overall Body Battery™ level. Like a gas gauge on a car, it indicates your amount of available reserve energy. The Body Battery level range is from 0 to 100, where 0 to 25 is low reserve energy, 26 to 50 is medium reserve energy, 51 to 75 is high reserve energy, and 76 to 100 is very high reserve energy.

You can sync your device with your Garmin Connect™ account to view your most up-to-date Body Battery level, long-term trends, and additional details (Tips for Improved Body Battery Data).