A wearable system based on fiber Bragg grating for monitoring respiratory and heart activity of archers

This study focuses on the monitoring of respiratory and heart activities on archers. These activities are linked with performance in precision sports since they can compromise the postural stability. In particular, soft sensors based a fiber Bragg grating (FBG) embedded into a Dragon Skin 10 polymer brick (90 mm length, 24 mm width, 1 mm thick) have been proposed to instrument a wearable system. The movements of the chest wall due to respiratory and the cardiac activities are transmitted through two bands housing an FBG. The consequent change of the FBG output provides an indirect method to monitor respiratory and heart activities.The positions of the instrumented bands on the athlete have been optimized by processing biomechanical data recorded on four archers during the shooting phase and quiet breathing. Then, we investigated the capability of the system to monitor respiratory- and cardiac-induced movements of the chest wall. Tests were performed on two volunteers during different respiratory phases and the simulation of the shooting phase.The output of the two instrumented bands reflects the chest wall movement due to respiration and cardiac pumping (during apnea). These results can be considered the first step toward the analysis of the relationship between archer's performance and cardiorespiratory activity. Besides, the use of the proposed system may be beneficial for analyzing the influence of the mentioned physiological activities on the performance in precision sports athletes.