Effect of Contact Pressure on the Accuracy of Photoplethysmography (PPG) - based Heart Rate Measurement During Activities on Black Skin

The accuracy of photoplethysmography (PPG) based heart rate (HR) measurement on dark skin is an important topic in remote health monitoring. In this study, I investigate the effect of contact pressure on PPG-based heart rate measurement on dark skin using a wrist-worn heart rate measuring device (in particular, a laboratory prototype). I found that the optimum contact pressure for PPG based heart rate measurement on dark skin is 60 mmHg, which is a bit higher than the optimum pressure of 54 mmHg for white skin reported in previous studies. This can be due to the increased melanin content in dark skin, which causes light absorption and scatter. This results in a lower signal-to-noise ratio (SNR) and thus a higher contact pressure is required to ensure accurate heart rate measurement. My results demonstrate that the contact pressure plays a crucial role in the accuracy of PPG based heart rate measurement on dark skin and should be considered in the design of remote health monitoring devices. The use of remote heart rate measurement can reduce mortality rates by providing early detection of cardiovascular diseases. This is especially important for athletes, who are at a higher risk of heart disease due to their intense physical activity. Wrist-worn heart rate monitoring devices are becoming increasingly popular among athletes as they are convenient and easy to use. However, the accuracy of these devices on dark skin has been a concern. My study contributes to the understanding of how contact pressure affects PPG-based heart rate measurement on dark skin, providing insights on how to optimize the design of wrist-worn heart rate monitoring devices for athletes with dark skin. The present findings have important implications for the design of remote health monitoring sensors/devices and can contribute to reduce mortality rates by providing early detection of heart disease. The study also has applications in the field of sports medicine, where wrist-worn heart rate monitoring devices are widely used by athletes.