Research: Wearables, including Apple Watch, are poor at tracking calories

In a paper published in January this year, researchers try to evaluate the usefulness of wrist-worn smart devices for tracking energy expenditure and heart rate. The Apple Watch Series 6, Polar Vantage V and the Fitbit Sense were used by 30 healthy male and female participants engaging in weight training, cycling, running walking and even sitting. As reference devices, the team used the Polar H10 chest strap and the MetaMax 3B.

We won’t go into detail about the research or the methodologies used, as these seem well-founded. Instead, we’ll talk about the results. The Stronger team from Science compiled it into an easy table to evaluate the reliability, accuracy and variability of each device.

It turned out that all the watches were terrible at keeping track of calories for almost every activity. Not only that, but the average deviation from the actual daily expenditure was unpredictable and wildly varying rendering the watches useless at tracking calories. That’s because you can’t reliably track progress even if absolute values are off. The wearables seem to be more inconsistant for individuals with lower than average and higher-than normal energy consumption.

The research seems to have been in keeping with other attempts to evaluate the same capabilities using different wrist-worn devices.

The good news is the Apple Watch Series 6 was pretty reliable in tracking heart rate across all activities. Polar Vantage V, and Fitbit Sense watchables show a variation depending on how hard you exercise. Steps count also seems to be on point for all of the devices involved in the research.

The bottom line? Despite its limitations, such as the small sample size of devices and individuals, the research seems to be in line with previous ones suggesting that the commercially available smartwatches and wrist-worn fitness trackers don’t provide reliable measurements of your daily energy expenditure. Moreover, they are highly unpredictable.

However, features such as heart rate monitoring and steps counting can be very useful and reliable. Research suggests smart watches alone can have a positive effect on your fitness. People who use smart wearables tend to increase overall activity and steps count.

Source | Via