Towards Athlete Fatigue Assessment from Association Football Videos
This work addresses fatigue monitoring for football athletes by offering a low-cost, non-intrusive alternative to existing methods, though it is incremental as it builds on existing Game State Reconstruction techniques.
The paper tackled the problem of assessing athlete fatigue in association football by proposing a method to extract kinematic signals from monocular broadcast videos, showing that these signals can be used for acceleration-speed profiling to indicate fatigue, with evaluation on the SoccerNet-GSR benchmark revealing compatibility with kinematic patterns but sensitivity to video noise and errors.
Fatigue monitoring is central in association football due to its links with injury risk and tactical performance. However, objective fatigue-related indicators are commonly derived from subjective self-reported metrics, biomarkers derived from laboratory tests, or, more recently, intrusive sensors such as heart monitors or GPS tracking data. This paper studies whether monocular broadcast videos can provide spatio-temporal signals of sufficient quality to support fatigue-oriented analysis. Building on state-of-the-art Game State Reconstruction methods, we extract player trajectories in pitch coordinates and propose a novel kinematics processing algorithm to obtain temporally consistent speed and acceleration estimates from reconstructed tracks. We then construct acceleration--speed (A-S) profiles from these signals and analyze their behavior as fatigue-related performance indicators. We evaluate the full pipeline on the public SoccerNet-GSR benchmark, considering both 30-second clips and a complete 45-minute half to examine short-term reliability and longer-term temporal consistency. Our results indicate that monocular GSR can recover kinematic patterns that are compatible with A-S profiling while also revealing sensitivity to trajectory noise, calibration errors, and temporal discontinuities inherent to broadcast footage. These findings support monocular broadcast video as a low-cost basis for fatigue analysis and delineate the methodological challenges for future research.