The proper execution of the sprint start is crucial in determining the performance during a sprint race. In this respect, when moving from the crouch to the upright position, trunk kinematics is a key element. The purpose of this study was to validate the use of a trunk-mounted inertial measurement unit (IMU) in estimating the trunk inclination and angular velocity in the sagittal plane during the sprint start. In-laboratory sprint starts were performed by five sprinters. The local acceleration and angular velocity components provided by the IMU were processed using an adaptive Kalman filter. The accuracy of the IMU inclination estimate and its consistency with trunk inclination were assessed using reference stereophotogrammetric measurements. A Bland-Altman analysis, carried out using parameters (minimum, maximum, and mean values) extracted from the time histories of the estimated variables, and curve similarity analysis (correlation coefficient > 0.99, root mean square difference < 7 deg) indicated the agreement between reference and IMU estimates, opening a promising scenario for an accurate in-field use of IMUs for sprint start performance assessment.
Elena Bergamini is with the Department of Movement, Human and Health Sciences, University of Rome “Foro Italico,” Rome, Italy, and with the Laboratoire de Biomécanique, Arts et Métiers Paris Tech, l’UFR Santé, Médecine, Biologie Humaine, Paris, France. Pélagie Guillon, Hélène Pillet, and Wafa Skalli are with the Laboratoire de Biomécanique, Arts et Métiers Paris Tech, l’UFR Santé, Médecine, Biologie Humaine, Paris, France. Valentina Camomilla (Corresponding Author) and Aurelio Cappozzo are with the Department of Movement, Human and Health Sciences, University of Rome “Foro Italico,” Rome, Italy.