“…Heart rate monitoring (HRM) data were collected in this trial using electrocardiography (ECG) [2] , [3] , [4] , photoplethysmography (PPG) [5 , 6] , and heart-rate belt (HRB) (Garmin HRM Dual, Garmin Ltd, Olathe, KS, USA) devices. ECG electrodes were located on the subject's chest in the space between the shoulder joint and thoracic cage under both left and right clavicles, and on the abdomen on the opposite side to the EIT reference electrode (on the parasagittal plane in line with the umbilicus).…”