Apple Watch Gets One Crucial Fitness Metric Wrong, Researchers Say

A new study analyzed 56 previous studies on the Apple Watch's accuracy in tracking heart rate, step count, and calories burned. The study found that the watch is highly accurate in tracking heart rate and step count, but significantly off in estimating calories. The average error in heart rate was 4.43%, and 8.17% for step count, which is considered acceptable. However, the error in calorie estimation was 27.96%, more than three times the acceptable margin. The high error margin was consistent across all Apple Watch models and user groups. The study suggests that while the Apple Watch is useful for tracking habits and motivation, the calorie estimates should be taken as a guide rather than a diagnostic tool. The study's findings align with previous evaluations that have raised concerns about the reliability of calorie burn estimates from consumer-grade wearables. Despite improvements over time, the Apple Watch still exhibits considerable error in calorie estimation. The study aims to inform consumers and smartwatch makers about the limitations of wearables and guide improvements.