Journal of Human Sport and Exercise

Comparisons in heart rate readings between the Bioconnected wireless exercise earpiece and a Polar T31-Coded Chest Strap during a GXT

Trevor R. Higgins, Thomas Lloyd, Kenneth Manalansan, Sara McDonald, Ben Thomas



Purpose. The advent of mobile technology has provided a convenient method of measuring heart rate in clinical settings and athletic training with limited support. Therefore the purpose of this research was to evaluate the validity of an earpiece HR monitoring device against a previously validated chest strap HR monitoring device. Method. A convenient sample of college students (n=15), performing a modified Bruce protocol, provided 25 data samples. Heart rates obtained from both the Bioconnected wireless exercise earpieces and a Polar T31-Coded Chest Strap where compared by correlation and coefficient. The Bioconnected wireless exercise earpieces were considered to be valid if the correlation between the recorded heart rate of the Bioconnected device and the corresponding heart rate Polar T31-Coded Chest Strap measurement was r ≥0.90. Results. Five samples were corrupted due to displacement of chest strap (n=3) and dislodgement of earpiece (n=2) during testing, as such data from those tests were excluded from the correlation analysis. The remaining 20 data samples provided mean totals of 521±117 HR data points (earpiece) and 517±118 HR data points (chest strap). A strong correlation (r=0.97) between the Bioconnected wireless exercise earpieces and a Polar T31-Coded Chest Strap. Conclusions. The results of this study show that the HR measurements of the Bioconnected wireless exercise earpieces and the Polar Chest Strap are highly correlated, supporting the Bioconnected wireless exercise earpieces in monitoring HR during a GXT on a treadmill in healthy adults. However, as exercise transitioned from walking to jogging, at times, both devices had problems with displacement and loss of HR signal, suggesting the need for improved methods of securing both devices. Future research of the Bioconnected wireless exercise earpiece is required to evaluate performance in varying environments, levels of low light and increased background noise. 


Heart rate monitoring; Validity; Polar monitor; Photoplethysmography; PPG


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