Two key developments in 2020 have created a sudden buzz around blood oxygenation and your SpO2 readings — COVID-19 and the debut of the Apple Watch 6.

Sixth generation Apple WatchApple Watch 6
Atom Tech Shorts Monday, October 12, 2020 - 20:20

Two key developments in 2020 have created a sudden buzz around blood oxygenation and your SpO2 readings — COVID-19 and the debut of the Apple Watch 6 that’s riding heavily on its Blood Oxygen Sensor. 

In simple terms, SpO2 refers to oxygen saturation, an estimate of the amount of oxygen in the blood. An acceptable SpO2 value is between 90 to 100% (95 to 100% being ideal) indicating good blood oxygenation that is necessary to supply the energy your muscles need to function. Fitness watches like Garmin have kept tabs on this because the pressure on your muscles increases during sporting activity. If your levels drop below 90%, it is a cause of concern, a sign of poor blood oxygenation or hypoxia. If a person has a mild case of COVID-19 and is self-isolated at home, SpO2 readings are a handy tool to monitor any dip in oxygen levels. But it’s more than just COVID, SpO2 readings are useful for those with active lifestyles or anyone who suffers from sleep apnea. 

Pulse oximeters (it’s why you will find some smartwatches also tout it as a Pulse Ox feature) date back to the 1930s but really took off in the 1970s. SpO2 is measured by Pulseimetry, a non-invasive method that emits and then absorbs a light wave passing through blood vessels. Clinical gadgets use a clip-on device that attaches to your finger (or even your earlobe). They depend on the variation of the light wave passing through the finger that generates the value of the SpO2 measurement. The degree of oxygen saturation causes variations in the blood’s colour. A growing number of smartwatches are now kitted with Optical SpO2 sensors that use red and infrared light sensors that analyse the colour of your blood. The degree of oxygen saturation causes variations in the blood’s colour.

Smartwatches with SpO2 sensors 

Apple Watch 6: the headline feature of the sixth generation Apple Watch. Apple’s Blood Oxygen sensor compensates for natural variations in the skin and improves accuracy by  employing four clusters of green, red, and infrared LEDs, along with the four photodiodes on the back crystal of  Apple Watch, to measure light reflected back from blood. The Apple Watch then uses an advanced custom algorithm built into the Blood Oxygen app, which is designed to measure blood oxygen between 70% and 100%. The Watch 6 offers both on-demand measurements that can be taken when the user is still and periodic measurements when they are inactive including during sleep. (Rs 40,900 onwards).

Samsung Galaxy Watch 3: The Galaxy Watch 3 comes with a sleeker form factor and is one of the best premium options for Android users. Samsung showed off a bunch of wellness features during the launch of its flagship wearable. The Watch’s ECG and Blood pressure monitoring are still awaiting regulatory approvals but the SpO2 sensor works seamlessly and on demand. Galaxy Watch3 uses red LED and infrared rays to estimate your SpO2 levels.  (Rs 29,990 onwards) 

Fitbit Versa 2: Fitbit’s all-new Sense smartwatch is the brand’s most ambitious product with a slew of wellness features. While you wait for this wearable to debut in India, you could also check this out on the brand’s Versa and Versa 2 smartwatches. Fitbit doesn’t offer spot checks, its SpO2 sensors are linked to sleep data. A new watch face displays your SpO2 readings almost by default. (Rs 21,999 onwards) 

Huawei GT2e: delivers quite a few fitness features at a compelling price point. It’s 5ATM water-resistant, allowing you to plunge into the pool and track your swim aside from multiple types of workouts that include indoor rowing and outdoor runs. The GT2e is powered by the Kirin A1 chip that has been created specifically for wearables. This wearable also supports single-time, on-demand SpO2 level measuring to monitor your Blood Oxygen levels (Rs 11,990) 

Garmin Fenix 6 Solar: Garmin has remained a cult favourite among serious fitness enthusiasts. The Fenix 6 Solar series integrates solar power and the unique Power Manager System with a battery life of up to 120 days. Garmin has also incorporated a reliable Pulse Ox Blood oxygen sensor into its flagship watches like the Fenix 6 Solar. The Garmin solution also measures how your body’s oxygen levels adjust to thinner air at higher altitudes (Rs 84,990) 

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