Smartwatches offer little insight into stress levels, researchers find | Smartwatches

They are supposed to monitor you throughout the working day and help ensure that life does not go up.

But a study has concluded that smart watches cannot precisely measure your stress levels – and may think that you are overworked when you are really excited.

The researchers found almost no relationship between the stress levels reported by the smartwatch and the levels that the participants said they had experienced. However, the levels of recorded fatigue had a very slight association with the smartwatch data, while sleep had a stronger correlation.

Eiko Fried, an author of the study, said that the correlation between the intelligent watch and the self -depressed stress scores was “fundamentally zero”.

He added: “It is not a surprise for us since the watch measures the heart rate and the heart rate does not have much to do with the emotion you feel – this also increases for sexual excitation or joyful experiences.”

He noted that his Garmin had already told him that he was stressed when he trained in the gymnasium and that he spoke enthusiastically to a friend whom he had not seen for some time at a wedding.

“The results raise important questions about what portable data may or cannot tell us about mental states,” said Fried. “Be careful and do not live according to your smartwatch – these are consumption devices, not medical devices.”

Fried said that although there has been a lot of academic work in search of physiological signals which can act as proxies for emotional states, most were not precise enough. Indeed, there is overlapping between positive and negative feelings – for example, standing hair can signal anxiety as well as excitement.

Fried, an associate professor in the Department of Clinical Psychology at the University of Leiden in the Netherlands, and his team followed stress, fatigue and sleep for three months out of 800 young adults with Garmin Vivosmart 4. They asked them to report four times a day on how stressed, tired or sleeping users felt before reference.

And the results, published in the Journal of Psychopathology and Clinical Science, revealed that none of the participants saw the stress scores on their watches will meet for a significant change when they have recorded a feeling of stress. And for a quarter of the participants, their smartwatch told them that they were stressed or not stressed when they appeared in contrast.

The relationship with physical fatigue, described by Garmin as a “body battery”, was “a little stronger than for stress but overall quite weak,” said Fried. Garmin does not disclose the calculations he uses to develop the score of the body battery, although it suspected that it was a combination of levels of measurement and impulse activity.

The relationship with sleep was again stronger, although Fried noted that it was measuring the duration of the sleep and told us little about how someone was good, except that there was a relationship between the duration of your sleep and the way you felt.

There was a significant association between the Garmin and the self -depressed data for two thirds of the sample for sleep. The researchers noted that in almost all cases, if the participants spent a day of poor quality of sleep to another day with a good score, they could predict an increase in the duration of sleep on the Garmin of about two hours. “It’s a really notable effect,” they said.

Research is intended to feed an early alert system for depression, in which users of portable technologies receive data that will help them receive preventive processing before the start of an episode.

Until now, there are promising signs that lower activity levels could be a predictor, although Fried has not been able to identify whether this is due to the protective effect of the exercise against depression or because people feel less energetic because their mental state is deteriorating.

“Portable data can provide valuable information on people’s emotions and experiences, but it is crucial to understand its potential and its limits,” said Margarita Panayiotou, researcher at the University of Manchester, after reading the study.

“This research helps to clarify what this data can reveal reliably and make an important contribution to the current discussions on the role of technology in understanding well-being. It is important to remember that portable data does not necessarily represent the objective truth and must be interpreted in parallel with a broader context, including the perceptions of individuals and lived experiences. ”

Garmin was approached to comment.