The latest struts use sweat to detect tension – this’s how it works

Nearly a year into the pandemic, it seems like the right time to commit to getting stress levels under control. (If it is not now, is not it?) And because we are a culture obsessed with personal data (consciously aware of our step count, calories consumed and hours we slept), it is not exactly surprising that the latest portable materials on the market do not detect voltage. . While different tech companies are doing this in different ways, one emerging method of detecting stress is through sweat – this is how the Fitbit Sense ($ 279) does it.

Although very noisy and cool, many people want to know exactly how this type of new technology works before they shoot out $ 300 – especially if you stress to the point where your shirt is soaked, you do not need a portable to tell you not that you need to calm down. While tension for sweat is a new concept for most, it’s something that nanotechnology researcher Mihai Adrian Ionescu, PhD, head of Nanolab and professor at the Swiss Federal Institute of Technology, has been studying for a while – and fits. published an article setting out the connection in the magazine. Nature. Here, together with Fitbit research algorithm scientist Belen Lafon, PhD, he provides more information.

© Photo: Getty Images / Westend61
tension of sweat

How sweat-from-stress detection works

Dr. Ionescu explains that stress – both physical and mental – initiates a reaction in the body and prepares it to face the stressor. One of the answers is sweat. But when we sweat, it’s not just water that leaks out of our pores. Cortisol – also known as the stress hormone – is also secreted. According to us, cortisol can be detected in our blood, sweat, saliva and urine. (Aren’t you glad the latest portable material doesn’t keep an eye on your puddle?)

In the experiments of Dr. Ionescu created his team a chip that detects changes in cortisol through sweating. “This process is very sensitive and effective in quantifying very small concentration changes,” says Dr. Ionescu. In other words: the chip detects very minimal changes in cortisol levels; you do not have to sweat a lot to detect that you are experiencing stress.

Here’s another thing to keep in mind: cortisol levels naturally fluctuate over the course of 24 hours. (Generally, it is higher in the morning when you wake up at the end of the day and lower.) Ionescu says his team’s technology takes this into account, as well as if someone secretes cortisol due to physical activity. “Abnormal cortisol levels can indeed be generated by stress, but also by intense physical activity,” he says. “There is a circadian rhythm of cortisol, but we know the ‘normal’ limits well … In addition, the technology will allow quantitative measurements over several days, so the recurrence of abnormal monitoring may confirm that it is due to stress. ‘

For example: if you meet with your boss every day at 14:00, the technology may record a change in cortisol levels during this time. Since this is not a time of day when cortisol levels usually rise in people and you do not exercise, the logical conclusion is that the cortisol changes are due to mental stress.

Dr Lafon says that Fitbit’s technology follows a different approach. “We approach stress management holistically, so we do not follow the rise and fall of individual hormones or bio-indicators, such as cortisol,” she says. Instead, she says the Fitbit Sense is the first smartwatch with a sensor that detects electrodermal activity (the variation of the electrical conduction of the skin in response to sweat secretion).

“Because sweat is good at conducting electricity, the more sweat you have, the easier the electric current will flow from one of the Sense electrodes to the other, so we can measure your skin conductivity, also known as your EDA response,” she says. “Sweat can be generated by different mechanisms, one of which is through small sweat waves – so small that it is not usually considered by us as ‘sweat’. These waves can be measured by Sense, and each one we call an EDA response. Measuring these responses can help users understand their body’s response to stressors and can help them deal with their stress. ‘

The smartwatch also uses heart and sleep activity in conjunction with this to give an overall “score” for stress. “Sense users with Premium can see minute-by-minute variation of skin temperature while sleeping to see how your skin temperature changes throughout the night,” explains Dr. Lafon.

Dr. Lafon emphasizes that electrodermal activity is the most important factor in monitoring voltage for the device, while heart rate and sleep pattern also play a role. According to her, this is a more complete picture of someone’s stress towards cortisol changes alone.

You have the data, what now?

Telling your laptop that you are stressed is not exactly a solution: it is also important to know what to do with the information. “Stress is an almost universal experience, with more than one-third of the people worldwide reporting physical and mental side effects from stress,” says Dr. Lafon. “Especially during COVID-19, it’s more important than ever to understand and manage your body’s response to stress in order to avoid a long-term impact on your health and well-being,” she adds, emphasizing that she understands the body’s response to stress is the key to management. It. If a Fitbit Sense wearer gets a lower voltage, she says the Fitbit app will offer practical recommendations on how to get the score to a better place, such as recommendations on awareness and meditation. (Fitbit Premium offers awareness sessions with Headspace.)

While Dr. Ionescu’s chip is not yet a product on the market, he is personally excited about the potential of the technology to improve health. “[This type of technology] opens the untapped ‘3 Ps’ of healthcare: preventative, personalized and participatory, “he says. This will help providers deliver the best therapy at the right moment and enable preventative approaches, “says Dr. Ionescu. For example, a portable person may notice that someone is stressed before realizing it themselves. Then this information can be used. to suffocate it before it gets worse.Armed with the information, someone will know that they really need to focus on managing their stress in whatever ways work for them, whether through exercise, meditation or therapy.

This evolving technology is another example of how wearing wears more about us than we know about ourselves. Have no idea how far you walked while taking out the dog? Look at your stats. Wonder if you really got eight hours of sleep last night? Tech keeps the score. And now you can use it to determine when to relax. The only remaining question: What will this tell us next?

Oh hi! You look like someone who likes free workouts, discounts on cult-fave wellness brands and exclusive Well + Good content. Join Well +, our online community of wellness information, and unlock your rewards instantly.