The higher your body fat percentage, the less accurate your smartwatch is at measuring calories you burn when exercising – new study

Smartwatches are wearable devices used by nearly 100 million adults in the U.S.

(about 4 in 10) and approximately 560 million people worldwide to monitor health and fitness.

These devices typically include sensors like accelerometers, which track movement, and light-based sensors to estimate heart rate.

They combine this data with user information such as age, sex, height, and weight, then use an algorithm to estimate calories burned during exercise.

While these features are widely used, research shows that the calorie estimates provided by smartwatches are often inaccurate.

A study by Florida International University’s Medical Photonics Laboratory found that the accuracy of these estimates varies significantly depending on the wearer’s body fat percentage.