Verity sense

The Polar Verity Sense is a PPG device. It is an optical heart rate sensor designed to be worn on the upper arm. The sensor materials include ABS, ABS + GF, poly(methyl methacrylate) (PMMA), and steel use stainless (SUS) 316. The device was positioned with the sensor on the underside of the armband and firmly against the skin. The Polar Verity Sense has a sample rate of 135 Hz and was connected to an iPad mini via Bluetooth.

Resting heart rate assessment: The participants’ resting heart rates were measured using a telemetric heart rate sensor (Polar Verity Sense; Kempele, Finland). After wearing the heart rate sensor, the participants remained in a sitting position for 20 min, and the lowest heart rate measured in the last 5 min was recorded as the resting heart rate (RHR). While the participants were waiting in a sitting position, they were not allowed to do any activity that could increase their heart rate (talking, playing with their mobile phone, etc.) [38 ].
Blood pressure measurement: Blood pressure measurements are critical tools for monitoring individuals’ cardiovascular health and detecting potential problems early. The blood pressure was assessed using an Omron HEM 742 automated oscillometric sphygmomanometer (Kyoto, Japan). The protocol was created by the American Heart Society [39 (link)] and was used to measure the blood pressure of the participants.

We used two POLAR® sensors (POLAR® Electro Oy, Kempele, Finland): the H10 chest strap (Model: 1W) as well as the Verity Sense (VS, Model: 4J), an optical (photoplethysmography: PPG) heart-rate sensor, to measure the participants’ heart-rate continuously during sleep. Both sensors are affordable (link),34 (link),35 (link)].
We used the NUKKUAA™ App for the sleep training program that recently has been developed as a Spin-Off from the University of Salzburg for Android and iOS mobile devices. During the sleep training study, only the H10 was used to capture sleep objectively. The H10 was connected to the user’s own smartphone and the NUKKUAA™ App via Bluetooth. Participants were instructed to start each recording by pressing the “Go to sleep” button on the home screen just before sleep and stop it accordingly upon awakening in the morning using the “Wake up” button.