Post-exercise heart rate variability in the acceleration photoplethysmogram

There is a limited number of studies on heart rate variability (HRV) dynamics immediately after exercise. It is well-known that the electrocardiogram is a non-invasive method that can be used to measure heart rate variability (HRV) at rest and after exercise. Photoplethysmogram (PPG) signals also reflect the cardiac rhythm since the mechanical activity of the heart is coupled to its electrical activity. Photoplethysmography is a non-invasive, safe, and easy-to-use technique that has been developed for experimental use in vascular disease. In this study, HRV has been investigated over 27 healthy subjects measured at rest and after exercise using PPG signals. The use of the aa interval in APG signals showed very promising results in calculating the HRV statistical indices, SDNN and rMSSD. Moreover, the after exercise SDNN and rMSSD indices have shown negative correlation with age.