Development and validation of a single wrist mounted inertial sensor for biomechanical performance analysis of an elite netball shot

The primary objective of the game netball is to score more goals than the opposition. Subsequently, there is impetus on improving shooting accuracy to maximize scoring. Understanding the kinematic factors of shooting that lead to scoring success allows for iterative adjustment and optimization of technique. Three-dimensional retro-reflective motion capture has been used to assess kinematics; however, these systems are expensive, require substantial setup and postprocessing time, and cannot be used in game-such as environments. With modern advancements in wearable microelectromechanical systems based technology, the ability to monitor shooting kinematics in the performance environment has become possible. This article evaluates the efficacy of a single wireless inertial measurement unit (IMU) sensor to monitor shooting kinematics, in terms of forearm angle at ball release. Four elite female shooters shot a total of 30 shots each (totaling 120 shots) from three different distances wearing both reference retroreflective motion capture (Vicon) markers and an IMU. To assess whether wearing the IMU had adverse effects on the kinematic shooting chain, a further ten shots each were taken without wearing the IMU. When contrasted with the gold standard reference of retro-reflective motion capture, the IMU sensor overestimated the forearm angle at ball release established by a mean percentage error of 4.03 ± 1.58%. Shots with and without the IMU indicated that the IMU did not biomechanically alter the shooting action. Important advantages of using IMU's over motion-capture solutions include that they are ubiquitous, low cost, require minimal user intervention, and can be used in representative training environments under defensive pressure. This information can enhance the understanding of the athlete's distal segment coordination patterns, providing actionable insights to enable performance to athletes and coaching staff.