New findings from a study conducted at the Canadian Sport Institute in Calgary, Canada validate the accuracy of blood oxygen saturation readings from Polar Elixir™ sensor fusion technology available on Polar Vantage V3 and Polar Grit X2 Pro.
Polar added SpO2 measurement capabilities to its Vantage 3 and Grit X2 Pro sport watches with the introduction of Polar Elixir™ sensor fusion technology, enabling users to monitor their blood oxygen saturation non-invasively. To validate the accuracy of this new feature, a study was conducted at the Canadian Sport Institute in Calgary, focusing on the Polar Elixir™ pulse oximetry technology integrated into the device.
The study aimed to evaluate how closely the Polar Elixir™ pulse oximeter's peripheral oxygen saturation (SpO2) readings matched arterial oxygen saturation (SaO2) measurements during a controlled hypoxia environment.
The researchers followed the International Organization for Standardization (ISO) protocol for SpO2 accuracy evaluation, which required testing at five different levels of SaO2 ranging from 70% to 100%. These levels were achieved through stepwise reductions in inspired oxygen while participants rested in a supine position.
Blood samples were taken from 25 participants using a radial arterial catheter to obtain SaO2 values, which were then compared with SpO2 readings from the Polar Elixir™. Initially, the root mean square error (RMSE) for the Polar Elixir™ was found to be 4.13%. However, after recalibrating the device's algorithm using SaO2 data from 13 randomly selected participants, the RMSE improved significantly to 2.67%. The study also revealed strong agreement between SaO2 and Polar Elixir™ SpO2 measurements. Before recalibration, the intra-class correlation (ICC) showed excellent agreement (ICC(1,3) = 0.837, df = 574, P < 0.001). Post-recalibration, the agreement improved further (ICC(1,3) = 0.942, df = 287, P < 0.001).
In conclusion, the Polar Elixir™ technology demonstrated accurate SpO2 measurements during stepwise inspired hypoxia at rest, with even greater precision achieved after algorithm recalibration. These findings confirm that the Polar Grit X2 Pro and Polar Vantage 3, both powered by Polar Elixir™ fusion sensor technology, offer reliable blood oxygen monitoring, making it a valuable tool for athletes and health-conscious individuals alike.
Reference
Russell, Monica K.; Horton, John F.; Clermont, Christian A.; Demarty, Jennifer M.; Transfiguracion, Leo C.; Worobets, Breann R.; Pineda, Mark E.; Santaniemi, Nuutti; Stergiou, Pro; Asmussen, Michael J.; Day, Trevor A.
Medicine & Science in Sports & Exercise. 56(9):1585-1594, September 2024.