Lionheart bands use an industry-standard algorithm to estimate caloric burn based on this study.
Women:
Caloric Burn = T × (0.4472×H - 0.1263×W + 0.074×A - 20.4022) / 4.184
Men:
Caloric Burn = T × (0.6309×H + 0.1988×W + 0.2017×A - 55.0969) / 4.184
Where:
T – Duration of exercise in minutes;
H – Your average heart rate in beats per minute;
W – Your weight in kilograms; and
A – Your age in years.
All wearables have slightly varied hardware and software approaches to estimating calorie burn, and a range of factors such as body type, skin tone, age and more can have an effect on the accuracy of wearable calorie estimates.
The best way to use calorie burn estimates is to identify trends over time that indicate progressive improvements in efficiency. Typically, a person will reduce calorie burn for the same activity over time as their body adapts to it and becomes more effective at cardiovascular exertion.