Accuracy of the iPhysioMeter Heart Rate Monitoring Application

Abstract

Standard heart rate (HR) monitoring pulse oximeters use light sensors to acquire HR data through photoplethysmography (PPG). By employing a smartphone’s camera and processing software, a smartphone can measure HR with PPG. The current study investigated the accuracy of the iPhysi-oMeter smartphone app in measuring heart rate before, during, and im-mediately after exercise on a treadmill to determine whether exercise and associated increases in heart rate affected the app’s accuracy. Twenty-eight participants (aged 21 - 29 years) completed the study. Using a re-peated-measures design, HR was measured with the iPhysioMeter app on an iPhone 6s, a 12-lead electrocardiogram (EKG), and a pulse oximeter. The first three stages of the Bruce treadmill protocol were used for standardized exercise testing. Significant differences were found between elevated HR readings from the EKG and pulse oximetry at Bruce 3 and between the iPhysioMeter app and EKG at Bruce 2 and Bruce 3. No significant differences were found for resting values or for Bruce 1 for any of the HR devices. Results suggested HR monitoring apps are an attractive alternative to expensive HR devices because of their usability and affordability. However, because the iPhysioMeter app had limited accuracy with elevated HR during exercise, caution should be used if relying on the app to monitor HR during exercise.