Biomechanical assessment in front-crawl swimming using inertial wearable sensors

This thesis is focused on the application of wearable Inertial Measurement Unit (IMU) sensors in the biomechanical analysis of front-crawl swimming. The thesis investigated two different aspects of the swimming analysis: the estimation of the added mass of the swimmer (defined as the quantity of water displaced during the athletic action, which increases water resistance) and the detailed kinematics of the upper limbs during front-crawl. Thus, the first study utilizes a single IMU device placed on the fifth lumbar vertebra and aims to test six different sensor fusion algorithms. Its objective is to determine the velocity profile from a stationary position to maximum velocity and to use the data obtained from this profile to calculate the added mass of the swimmer. While, the second study seeks to ascertain the joint angles of the upper body kinematic chain (scapulothoracic, shoulder, and elbow joints) by attaching four IMUs to the rigid body segments of the thorax, scapula, arm, and forearm. This is done in order to gather accurate data on the swimmer’s technique during training and give important information to coaches and athletes.