🔗 Share this article

There's a nervous excitement. Apparent is the cold breath emanating from my fellow runners as they execute the "starting line" shuffle on the start line.

A rapid flick of the hips.

I'm participating in my local Saturday morning race and I'm focused. It's almost time...

Wait a second. I must sort my watch. The same goes for the person next to me.

The person behind us sighs. I refuse to go until… yes! GPS ready, away I go.

In the mele, it's hard to find a wrist without a wearable on it. And this extends beyond us athletes who use them.

We're witnessing a thriving, massive market. Brands like Garmin lead the market, each with an extensive selection of diverse models to cater to a range of budgets. Based on how high tech the model you go for, costs can range from £100 to thousands of pounds.

"I find it infuriating, I'm unable to stop checking."

"It provides solace… It feels like a supporter encouraging me."

"Stop telling me about a bad night's sleep."

Just some of the comments I've had from fellow tracker enthusiasts when I question what they feel about theirs.

The Monitoring Conundrum

My thoughts on my own device? Currently, annoying. It's reporting my speed is wrong, leading me to doubt whether the overhead branches along my route are interfering with my location tracking.

Millions of us strap these small monitors onto our arms and use them all day and night, apparently unconcerned with the fact they're perpetually monitoring us.

Gone are the days when we depended on them only to give us an estimation of our pedometer reading. Now, they can measure our sleep quality, stress levels, heart rate variability (HRV), our VO2 max.

It's difficult to find a bodily function they aren't designed to measure.

But can they do what they claim to do? And are the statistics we analyse a faithful picture of our actual health? Do they improve our overall health, or do the multitude of readings and constant notifications just add to our everyday anxiety?

A Love-Hate Relationship

"I find myself getting a a little fixated with mine," an individual reveals.

While she loves how her device records her workouts, she finds some of its other functions "excessive" at times - a feeling initially realised during a significant period.

Until she found out she could put it into a specific mode, her smartwatch constantly alerted her she was not being energetic enough. In a new phase, the watch keeps telling her she's had a restless night.

"I've got a six-month old, it's unnecessary for me to be told I've not slept," she says. "I know that all too clearly."

Couldn't she just stop wearing it?

"I suppose I could, theoretically, but I have this love-hate relationship with it," she says. "I love it for its workout tracking, I just wonder whether the myriad other functions it can now do is perhaps overkill for me."

How Do They Work?

Each model of smartwatch has its own novel way of tracking your health metrics and interpreting your data, but the vast bulk use detectors on the underside of the watch.

They commonly project minute LED lights onto your arm which can monitor capillary action, detecting your pulse rate. More advanced devices analyse changes in the electrical current that flows through the skin to get an idea of your stress levels.

Expert Perspectives

A professor says that for most people for smartwatches, it's a "delicate equilibrium" - while the continuously improving tech could potentially aid early diagnosis, "spotting abnormalities before we notice anything", it could also turn us the tracked into the "worried well".

He points out that some of the latest wearables can conduct tests like medical-grade monitoring, which continuously monitor how normal the heart is. They can flag if someone is experiencing a heart arrhythmia, where there is abnormal electrical activity in the heart causing an arrhythmia.

This does not necessarily indicate someone is on the verge of a cardiac event, but it can give an early warning they might be more susceptible of a stroke in the long term.

But how to understand these numbers is complicated. The expert worries that as further capabilities are added, people may find it hard to fully contextualise their data.

"I have some doubts that being able to monitor so many metrics is such a positive development," he says.

A health researcher focusing on patient behaviour concurs. Research into the effect of wearable tech on a specific group of heart condition patients suggested a minority of those who were given devices to monitor their cardiac function experienced heightened worry and were "far more likely to use healthcare resources".

She noted a cycle with her patients - they spotted a concerning reading on their watch. They became worried. Their pulse went up. They got even more concerned. They checked again, and their anxiety went up again.

"When people are presented with data about ourselves that we can't properly interpret then, of course, we are going to want to know more," the psychologist says. "We look, we obsess - it becomes a feedback loop."