Use of an IMU Device to Assess the Performance in Swimming and Match Positions of Impaired Water Polo Athletes: A Pilot Study

In Paralympic sports, to guarantee fair competition, it is necessary to identify those peculiar abilities that characterize the discipline and the motor limitations that may or may not most affect the athlete’s performance in a specific sports task, assigning an appropriate classification to the level of impairment. This study proposes a minimally invasive assessment system based on a single inertial sensor to support the investigation of the peculiarities of water polo with disabilities by analyzing players’ trunk inclinations during a simulated match and angular speeds in swimming tests. By comparing a small group of athletes of various classes and those without disabilities, we intended to evaluate whether athletes with lower limb disabilities may be disadvantaged compared to athletes with upper limb disabilities. The results suggest no difference in the mean percentage of time in vertical and horizontal positions when comparing players with and without disabilities, although specific impairments led to distinct behaviors (Δ = 0.9%, p = 0.841). Interesting insights emerged in swimming and turning situations in the water. Strong correlations (r > 0.7, p < 0.05) were found between swimming performance metrics and classification points. Furthermore, players with spasticity exhibited lower smoothness in turning movements, suggesting less fluid execution than those with other impairments affecting the same limbs. These findings highlight the IMU system’s potential to provide objective, quantitative data for refining WPA classification protocols.