JMIR Publications

ABSTRACT

Background:

Biosensors and wearable systems are rapidly evolving, particularly in healthcare, due to their ability to facilitate continuous or on-demand physiological monitoring.

Objective:

This study aimed to design and validate a wearable biosensor prototype incorporating photoplethysmography (PPG) and LoRaWAN technology for heart rate (HR) measurement during a functional test.

Methods:

We conducted a transversal exploratory study involving 20 healthy subjects aged between 20 and 30 without contraindications for physical exercise. Initially, our laboratory developed a pulse biosensor prototype for HR monitoring. Following this, they were instructed to perform the Incremental Shuttle Walk Test while wearing the Polar H10 HR chest strap sensor (the reference for HR measurement) and the wearable biosensor. This allowed for real-time comparison of HR responses between the two devices.

Results:

The mean differences between the Polar H10 rest HR and the sensor during the test were as follows: -2.6 [95% CI: -3.5 to -1.8] for rest HR, -4.1 [95% CI: -5.3 to -3] for maximum HR, -2.4 [95% CI: -3.5 to -1.4] for mean test HR, and -2.5 [95% CI: -3.6 to -1.5] for mean recovery HR. The mean absolute percentage errors were -3% for rest HR, -2.2% for maximum HR during the test, -1.8% for mean test HR, and -1.6% for recovery HR. Excellent agreement was observed between the Polar H10 and the biosensor for rest HR (ICC3.1=0.96), mean HR during the test (ICC3.1=0.92), and mean recovery HR (ICC3.1=0.96). The agreement for maximum HR (ICC3.1=0.78) was considered good.

Conclusions:

The pulse wearable biosensor prototype tested in this study proves to be a valid tool for monitoring HR at rest, during functional tests, and during recovery when compared to the Polar H10 reference device used in the laboratory setting. Clinical Trial: Brazilian Registry of Clinical Trials (ReBEC, RBR-359p69v)