Apple Watch Calorie Estimates Miss by Up to 93% as Wearables Struggle to Measure Energy Burn
Updated
Updated · Engadget · Jul 26
Apple Watch Calorie Estimates Miss by Up to 93% as Wearables Struggle to Measure Energy Burn
1 articles · Updated · Engadget · Jul 26
Summary
Studies cited in the latest report found Apple Watch and similar wearables cannot reliably track calorie expenditure, with errors ranging from 27% for the best device to 93% for the worst.
Stanford researchers said heart-rate readings were accurate, but calorie burn was not because watches cannot measure metabolism directly and must infer energy use from proxies like heart rate, motion and distance.
Those estimates depend on machine-learning models that vary across fitness level, height and weight, while compounded sensor errors, skin tone and moisture can further distort results.
Apple Watch and rival devices still detect workouts by combining accelerometer, gyroscope, GPS and heart-rate data, but the report says their calorie counts remain educated guesses rather than dependable measurements.