Calories Burned

Accurate calorie counts for daily life, top performance, and everything in between.

What Is Calories Burned?

Knowing how many calories you burn gives you the power to make informed decisions about nutrition, weight management, and performance. How many calories you burn varies based on your personal background information and the intensity of your physical activities. Physiologists measure activity intensity in terms of the amount of oxygen your body is using. This is because your body uses oxygen in its aerobic energy generation process. It also allow intensity to be expressed as a percentage of your VO2max fitness level, which is important for understanding how your efforts relative to maximum capacity.

  • Based on the single best indicator of activity intensity
  • Personalized to match your unique physiology and activity levels
  • Accurate across the full range daily activities and intensity levels
  • Responds quickly and reliably to changes in intensity
Calories Burned

How Does It Work?

While heart rate alone can offer some insight into the number of calories your burn, it can also be misleading. This is because your heart rate is not influenced solely by the intensity of your physical activity. Stressful situations, for example, may produce an elevated heart rate, but that doesn’t mean that your body is burning calories at the same rate as during exercise.

The calculation Firstbeat Analytics uses to provide accurate calorie counts relies on a combination of heart rate, respiration rate derived from heart rate variability, and a third variable provided by the Firstbeat Analytics engine that allows the model to reliably detect current oxygen consumption as it corresponds to the intensity of your physical activity.

Energy Expenditure During Exercise Energy Expenditure All Day