SpO2 measurement
The SpO2 measurement feature uses pulse oximeter technology to estimate the amount of oxygen in your blood. Your body needs a constant supply of oxygen to perform properly. Your blood oxygen level (SpO2) shows how much oxygen your blood carries compared to its full capacity (100%). When you're at sea level and at rest, SpO2 between 95 % and 100 % is considered normal. Because of lower atmospheric pressure, SpO2 is lower at higher altitudes.
With the SpO2 measurement feature, you can measure SpO2 conveniently from your wrist whenever you want in 45 seconds. You can find the feature in the Tests menu of your watch. Regular SpO2 measurement allows you to monitor your usual SpO2 level in everyday life under normal circumstances. Knowing your usual level can help you understand how your body adapts to certain situations, such as high altitudes. If you're training at varying altitudes, you can use this measurement to monitor how your SpO2 changes and your body adapts to a new altitude.
The SpO2 measurement is not intended for medical or diagnostic use. If you have any concerns about your health, please contact a healthcare professional.
SpO2, which stands for Peripheral Oxygen Saturation, is an estimate of the amount of oxygen in your blood. More specifically, it indicates the percentage of hemoglobin that is saturated with oxygen (oxygenated hemoglobin) compared to the total amount of hemoglobin in the blood.
The feature uses pulse oximetry technology to estimate the amount of oxygen you have circulating in your blood. It emits two different wavelengths of light, red and infrared, through the skin and into the underlying blood vessels. Inside the blood vessels, the light interacts with the oxygenated and deoxygenated hemoglobin in the red blood cells. The amounts of reflected and backscattered light are used to calculate how much oxygen your blood is carrying.
You can measure your SpO2 while sitting or lying down. The position should always be the same when you perform the measurement. It is important to be in a relaxed, stable position that helps minimize movement, which can affect reading accuracy. If you perform the measurement while sitting, keep your arm in an open position on a table so that it does not touch your body to ensure that the movement caused by breathing does not interfere with the measurement. If you perform the measurement lying down, keep your arm by your side, but so that it does not touch your body. It is important that you keep your hand still.
Before starting the measurement:
- Make sure to wear the watch at least 10 minutes before the measurement.
- If your hands are cold, warm them up before the measurement.
- If you perform the test after training, it is recommended to rest for at least ten minutes before starting the test to allow your body to return to its normal state.
- Make sure that your watch is properly fitted: it should be worn a finger’s width behind the wrist bone and be tight enough that it won’t move around.
- Perform the measurement in similar conditions every time.
During the measurement:
- Keep your arm steady and relaxed until the timer runs out.
- Keep your body still. Movement during the measurement can lead to inaccurate readings.
- Avoid talking during the measurement.
Make sure your hand is not cold and you're wearing your watch snugly.
On your watch, go to Tests > SpO2, and then tap Measure now.
Keep your arm steady and relaxed until the timer runs out.
After the measurement, the following results will be displayed on your watch:
- Your blood oxygen level as a percentage.
- Altitude: Altitude during the measurement. To get accurate altitude readings, you need to calibrate the altitude. You can do this, for example, in the Navigation view of your watch. For instructions, see Navigation in the Choose views section of the user manual.
- Verbal description of your blood oxygen level: Your SpO2 is normal (95-100%) - Your SpO2 is below normal (90-94%) - Your SpO2 is low (<90%).
You can view your latest result on your watch in Tests > SpO2 > Latest result.
If the test fails, try moving your watch higher on your wrist. You can also try wearing the watch on your other wrist to see if that helps.
Sync your watch with the Polar Flow app to see your SpO2 measurements in the app.
Note that you must sync your watch using the Flow app. SpO2 measurements cannot be synced using the Polar FlowSync software on your computer.
You can check the SpO2 measurements for the current day from the Diary. Tapping the card opens a more detailed SpO2 measurement view. Tapping the list icon opens your previous SpO2 measurements in the calendar search view.
