Purpose: Classification is a defining factor for competition in wheelchair sports, but it is a delicate and time-consuming process with often questionable validity. New inertial sensor-based measurement methods applied in match play and field tests allow for more precise and objective estimates of the impairment effect on wheelchair-mobility performance. The aim of the present research was to evaluate whether these measures could offer an alternative point of view for classification. Methods: Six standard wheelchair-mobility performance outcomes of different classification groups were measured in match play (n = 29), as well as best possible performance in a field test (n = 47). Results: In match results, a clear relationship between classification and performance level is shown, with increased performance outcomes in each adjacent higher-classification group. Three outcomes differed significantly between the low- and mid-classified groups, and 1, between the mid- and high-classified groups. In best performance (field test), there was a split between the low- and mid-classified groups (5 out of 6 outcomes differed significantly) but hardly any difference between the mid- and high-classified groups. This observed split was confirmed by cluster analysis, revealing the existence of only 2 performance-based clusters. Conclusions: The use of inertial sensor technology to obtain objective measures of wheelchair-mobility performance, combined with a standardized field test, produced alternative views for evidence-based classification. The results of this approach provide arguments for a reduced number of classes in wheelchair basketball. Future use of inertial sensors in match play and field testing could enhance evaluation of classification guidelines, as well as individual athlete performance.
Rienk M.A. van der Slikke, Daan J.J. Bregman, Monique A.M. Berger, Annemarie M.H. de Witte and Dirk-Jan (H.) E.J. Veeger
Rienk M.A. van der Slikke, Annemarie M.H. de Witte, Monique A.M. Berger, Daan J.J. Bregman and Dirk Jan H.E.J. Veeger
Purpose: To provide insight on the effect of wheelchair settings on wheelchair mobility performance (WMP). Methods: Twenty elite wheelchair basketball athletes of low (n = 10) and high classification (n = 10) were tested in a wheelchair-basketball-directed field test. Athletes performed the test in their own wheelchairs, which were modified for 5 additional conditions regarding seat height (high–low), mass (central–distributed), and grip. The previously developed inertial-sensor-based WMP monitor was used to extract wheelchair kinematics in all conditions. Results: Adding mass showed most effect on WMP, with a reduced average acceleration across all activities. Once distributed, additional mass also reduced maximal rotational speed and rotational acceleration. Elevating seat height had an effect on several performance aspects in sprinting and turning, whereas lowering seat height influenced performance minimally. Increased rim grip did not alter performance. No differences in response were evident between low- and high-classified athletes. Conclusions: The WMP monitor showed sensitivity to detect performance differences due to the small changes in wheelchair configuration. Distributed additional mass had the most effect on WMP, whereas additional grip had the least effect of conditions tested. Performance effects appear similar for both low- and high-classified athletes. Athletes, coaches, and wheelchair experts are provided with insight into the performance effect of key wheelchair settings, and they are offered a proven sensitive method to apply in sport practice, in their search for the best wheelchair–athlete combination.