Longitudinal analysis of heart rate and physical activity collected from smartwatches

Smartwatches can continuously and autonomously monitor vital signs, including heart rates and physical activities involving wrist movement. The monitoring capability of smartwatches has several key health benefits arising from their role in preventive and diagnostic medicine. Current research, however, has not explored many of these opportunities, including longitudinal studies. In our work, we gathered longitudinal data, including heart rate and physical activity, from various brands of smartwatches worn by 1014 users. Our analysis shows three common heart rate patterns during sleep and two common patterns during the day. In addition, we aim to emphasize the practical application of our statistical methods, showcasing the valuable insights and patterns they reveal. We find that heart rate and physical activities are higher in summer and the first month of the new year compared to other months. Moreover, physical activities are reduced on weekends compared with weekdays. Interestingly, the highest peak of physical activity is during the evening.