How accurate are your wearables?

The first watch ever invented was around the 1500s by a locksmith named Peter Henlein from Nuremberg, Germany. Ever since then, the race to make watches more compact, smart, and accurate began. The watch in your hand slowly evolved into a machine that can not only tell you the time but also monitor your heart rate. Analog became digital, and soon digital became high-tech.
The first smartwatch was the Seiko Ruputer, which was launched in 1998 and could run applications and connect to a PC. By 2014, brands like Samsung and Apple had their own versions. Today, wearables or smartwatches have become common and are no longer limited to athletes.

Today, prices for smartwatches go as high as Rs 60-70,000. Photo: Unsplash

In India, you can find these smartwatches even on the street side for as low as Rs 100 or 150, making them more and more common.
Today, there are other similar cases where smartwatches have saved the lives of people. These wearables, such as smartwatches and fitness trackers, can monitor a variety of health and fitness metrics.
But are your wearables really accurate to the point, as they are marketed? Read ahead to find out.
In a recently published umbrella review (a systematic review of systematic reviews) experts examined scientific literature on whether consumer wearable devices can accurately measure metrics like heart rate, aerobic capacity, energy expenditure, sleep and step count. The review found that at a basic level, the accuracy of the devices is good.
The study found that wearables can measure heart rate with around 3% error, depending on factors like ‘skin tone and exercise type and if you have tattoos’. They also do well at detecting heart rhythm issues and estimating cardiorespiratory fitness, especially during exercise.
But
Experts also seem to agree with the analysis.
Dr Shrey Kumar Srivastav, a general physician at Sharda Hospital, says the accuracy of wearables, especially fitness trackers, can vary significantly depending on the device’s quality, sensor technology, and how it’s used. He lists some examples:
Heart rate monitoring: Some wearables rely on optical sensors, which measure blood flow through your skin. This method can be prone to inaccuracies if the wearable isn’t tight enough, if you have darker skin tones, or tattoos, or during intense activities.

Wearables tend to underestimate step counts by about 9%. Photo: Unsplash

Sleep tracking: Wearables often estimate sleep based on movement and heart rate, which may not always match clinical sleep study results. They can misjudge periods of rest as sleep or fail to identify different sleep stages.
Calories burned: This metric is particularly difficult to track accurately because it depends on many individual factors, including metabolism, fitness level, and type of exercise.
Talking about wearables, you must have also been bombarded with the latest kind of wearables which can do all the things that a smartwatch can do, but they are much smaller.
Yes, we are talking about smart rings. Rings, as a fitness accessory sound cool, but Dr Tushar Tayal, a consultant of internal medicine at CK Birla Hospital, Gurugram, says that even though rings are becoming popular due to their smaller size, they have smaller sensors, which may affect accuracy compared to watches.
“Like other wearables, the quality of data depends on the brand and technology used,” says Dr Tayal.
If wearing wearables is your thing, go for brands you trust, and not the roadside or the brands you’ve never heard of, as apart from being inaccurate, it can lead to other problems too.
Dr Tayal says it can lead to problems such as:
Think about why you want a wearable. Is it for tracking workouts, monitoring health metrics, or just for notifications? Knowing your goals helps narrow down your choices.
Research reviews and studies on how accurate the wearable is in the metrics that matter to you (e.g., heart rate, sleep, or GPS tracking).
Make sure the wearable integrates with apps and platforms you’re already using, such as health apps on your phone.
Look at how the company handles your data, particularly if you’re tracking sensitive health information.
While wearables can provide valuable health insights, their accuracy varies. Believe it when it tells you something is wrong with your heart, but for other things like your step count or calories burned in a day, take it with a pinch of salt. Keep in mind that it’s essential to invest in a trusted brand and carefully consider your needs before making a purchase.