Can a smartwatch keep your health in check?

Recently, Delhi-based policy researcher Sneha Sinha, was caught off guard when her smartwatch alerted her of an “abnormally high” heart rate. “As an avid traveller, I hike in high-altitude mountain regions above 15,000-16,000 feet where oxygen levels are often low,” shares Sinha, asserting that she did not have pre-existing medical conditions. “I tried deep breathing, hoping it would get resolved. When it persisted for over 1.5 hours, the ECG indicated the onset of Atrial Fibrillation (AFib). I then decided to seek medical attention,” she adds, explaining that the doctors had described her situation as a “close call”.

From tracking REM cycles during sleep to monitoring calorie intake on a night out, smartwatches have evolved beyond basic functions like internet browsing and calls. Advanced wearables now offer healthcare features such as in-built ECG readers, AFib History Optical heart sensors, blood-oxygen meters and more. A 2020 study published in JAMA Cardiology even suggests that some wearables could provide readings as accurate as traditional ECGs, potentially saving lives.

How does the tech work?

According to a study on ECG potential published in Science Direct, smartwatches use LEDs that flash against the skin to detect blood flow and measure heart rate. Sensors collect this information, which algorithms then process to make sense of the heart’s rhythm.

Expert advice: use it wisely not blindly

While wearable devices have clinical potential, medical professionals advise against using smartwatches as a baseline for their cardiovascular health.

“Two benefits compared to ‘medical’ 24-hour ECG or Holter monitoring are theconvenience of use and near-continuous monitoring. Although people can learn to monitor their own health, precision is a major limitation,” says Dr Rakesh Rai Sapra, director of cardiology, Marengo Asia Hospitals, Faridabad.

With the existing features, users can use their devices to learn to check for irregularities, says Dr DK Jhamb, director of interventional cardiology, SHALBY Sanar International Hospitals. “They are at best early indicators of overall cardiovascular health. If there is an irregular heartbeat, smartwatches usually give erroneous readings of low heart rate. If your heart rate is too fast (over 100 beats per minute) or too slow (slower than 60), get yourself checked by a cardiologist at the earliest,” he ends.

Establishing a baseline

Feed your exact height, weight, dietary changes and pre or post-surgical data that might affect your health to ensure accuracy.

Always seek medical attention to interpret the data being recorded and any irregularities.

If you choose a personalised fitness regimen, disclose any existing health conditions and keep in mind your health metrics.

Use your smartwatch as an indicative tool and avoid self-diagnosis

Inputs by fitness expert Chavi Dutt