🔗 Share this article

A sense of building tension. Visible is the frosty air coming from my fellow runners as they do the "about to run" shuffle on the starting line.

A quick flick of the hips.

I'm participating in my local weekly parkrun event and I'm focused. It's almost time...

Oh, hang on. I must adjust my device. As does the runner alongside me.

The person in the line expresses impatience. I won't start until… done! Connection established, I'm off.

In the mele, it's hard to find a wrist without a fitness tracker on it. And this isn't only us athletes who use them.

It's a thriving, massive industry. Brands like Garmin dominate, all offering an wide array of diverse devices to suit a spectrum of budgets. Based on how advanced the model you go for, costs can vary between £100 to a small fortune.

"It makes me crazy, I'm unable to stop checking."

"It provides solace… It feels like a companion guiding me."

"Please don't notify me I've experienced a restless night."

Just some of the reactions I've had from other tracker enthusiasts when I inquire what they feel about theirs.

The Data Dilemma

My feelings on my own device? At this moment, irritating. It's reporting my speed is wrong, leading me to doubt whether the foliage I'm running below are interfering with my satellite signal.

A vast number of us fasten these small monitors onto our wrists and wear them 24/7, ostensibly unconcerned with the fact they're continuously tracking us.

A distant memory are the days when we used them only to give us an rough count of our step count. Now, they can analyse our sleep quality, stress levels, oxygen saturation, our VO2 max.

It's tricky to find a bodily function they don't track.

But are they able to do what they claim to do? And are the numbers we obsess over a faithful picture of the truth? Do they boost our daily wellness, or do the avalanche of metrics and cheerleading alerts just increase our everyday anxiety?

Addiction or Aid?

"I do get a bit preoccupied with mine," an individual confesses.

While she appreciates how her device records her exercise, she finds some of its other features "daunting" at times - a feeling that became apparent during a major life event.

Before she realised she could change its configuration, her smartwatch kept telling her she was failing to be active enough. Later on, the watch frequently reports her she's had a bad night's sleep.

"I've got a infant, I don't need to be told I've not slept," she says. "That fact is perfectly well."

Why doesn't she just stop wearing it?

"I suppose I could, perhaps, but I'm in this complicated dynamic with it," she says. "I value it for its exercise data, I sometimes question whether the additional features it can now do is possibly too much for me."

How Do They Work?

Each model of smartwatch has its own proprietary way of measuring your bodily functions and analysing your data, but the majority use detectors on the back of the watch.

They typically project minute LED lights onto your wrist which can monitor pulsation, recording your heartbeat. Sophisticated devices measure changes in the skin conductance that flows through the skin to get an idea of your recovery state.

Expert Perspectives

One expert says that in general for smartwatches, it's a "delicate equilibrium" - while the ever-evolving tech could potentially prevent illness, "spotting abnormalities before we notice anything", it could also turn us the tracked into the "concerned but fine".

He points out that the most advanced wearables can carry out tests like heart rhythm analysis, which constantly monitor how healthy the heart is. They can flag if someone is experiencing an irregular rhythm, where there is abnormal electrical activity in the heart causing an uneven pulse.

This does not necessarily indicate someone is imminently going to suffer a heart attack, but it can give an advance notice they might be more vulnerable of a heart problem in the years to come.

But how to interpret these readings is complicated. The expert worries that as further capabilities are introduced, people may struggle to fully understand their data.

"I'm not entirely convinced that the ability to monitor so many things is such a good idea," he says.

A clinical psychologist specialising in wearable tech echoes this sentiment. A study into the influence of wearable tech on a set of heart condition patients suggested a minority of those who were given devices to monitor their heart health experienced increased anxiety and were "more inclined to use doctor's time".

She identified a pattern with her patients - they noticed a alarming metric on their watch. They grew concerned. Their heart rate went up. They got even more concerned. They looked a second time, and their heart rate rose further.

"If we see numbers about ourselves that we lack context for then, understandably, we are going to seek clarification," the psychologist says. "We monitor, we re-check - it becomes a feedback loop."