Experimental and applied approaches to characterize swimmers' hydrodynamics through wearable technologies

In a swimming race, victory depends on mastering hydrodynamic forces: maximizing propulsive force and minimizing hydrodynamic resistance. This thesis investigates the athlete–fluid interaction with the practical aim of assessing instrumentation and methodologies that are minimally invasive and highly applicable in sporting contexts. The work is structured around three integrated axes. (i) Propulsion: wearable, wireless pressure sensors that minimally impact the swimming technique are validated in terms of reliability and accuracy of pressure measurements, and force estimates are compared with a reference dynamometer during tethered swimming. The same tools are then applied to assess swimmers’ propulsive symmetry and to compare the force produced by the hand in free swimming versus in a full-tethered condition. (ii) Hydrodynamic resistance: an experimental protocol previously proposed in the literature to estimate front-crawl drag was extended to the analysis of other strokes, in order to experimentally validate the balance between propulsive and resistive forces at constant speed and to extract information on hydrodynamic resistance. In addition, an estimate of added mass, an inertial component that becomes crucial during acceleration and deceleration phases, is proposed through a more complex protocol that nonetheless has little impact on the technical gesture. (iii) Resistive parachutes: the hydrodynamic resistance of parachutes during their interaction with the swimmer is characterized, with the aim of controlling the additional load imposed by these devices during training. Some energetic implications of their use were evaluated, and an applied method for estimating drag during training was proposed. In summary, the thesis builds an operational bridge between the laboratory and practice, discussing the advantages and limitations of protocols, sensors, and computational tools that bring science closer to the pool and make key performance parameters measurable.