Linking field-based mobility tests to match-derived performance in wheelchair rugby: understanding test-match...

Field-based performance and skill tests are widely used in wheelchair rugby (WR) to assess physical capacity, yet their relation to in-game mobility and potential differences between athletes with and without coordination impairment (CI) remain unclear. This study examined (1) ecological validity and test-match correspondence of a comprehensive WR field-test battery, reflecting maximal capacity, against match-derived mobility performance, (2) impairment-based differences in test-match agreement, and (3) trunk-movement differences between CI and Non-CI athletes. Fifty-two international WR athletes (Non-CI: n = 27; CI: n = 25) completed a standardized battery (sprint, turning, stop-go, complex skills) with wheel- and trunk-mounted inertial sensors. Match metrics (e.g., average/maximal speed, rotational speed) were derived from full-match IMU data. Test-match correspondence was assessed using Pearson correlations and Lin's concordance; agreement with Bland-Altman analysis; group differences with Welch's t-tests (FDR/Holm corrected). Trunk angle and trunk-relative accelerations were analyzed separately, with classification included in supplementary analyses. Maximal forward speed showed strong association (20 m sprint: r = 0.878, small bias), and rotational capacity was best captured by an isolated 180° turn (r = 0.796). Acceleration metrics showed moderate correlations but poor absolute agreement, indicating they reflect maximal capacity rather than match-equivalent output. CI athletes showed smaller test-match discrepancies, whereas Non-CI athletes' tests tended to underestimate match speed and overestimate acceleration. Trunk-sensor outcomes differed strongly between groups (g ≈ 0.9-1.2), indicating substantial impairment-related variation. Classification correlated positively with performance, with similar strength across groups. Linear sprint and isolated turning tests show strong associations with in-game WR performance, while acceleration metrics mainly index maximal capacity. Field tests appear to align more closely with match behavior in CI athletes than in Non-CI athletes. Trunk-sensor measures add value for profiling and may support future classification.