Open Access

David Friebe, Johanna Sieland, Hendrik Both, Florian Giesche, Christian Haser, Thorben Hülsdünker, Florian Pfab, Lutz Vogt, Winfried Banzer

• Agility, as the ability to react rapidly to unforeseen events, is an essential component of football performance. However, existing agility diagnostics often do not reflect the complex motor–cognitive interaction required on the field. Therefore, this study evaluates the criterion and ecological validity of a newly developed motor–cognitive dual-task agility approach in elite youth football players and compare it to a traditional reactive agility test. Twenty-one male youth elite football players (age:17.4 ±0 .6; BMI:23.2 ± 1.8) performed two agility tests (reactive agility, reactive agility with integrated multiple-object-tracking (Dual-Task Agility)) on the SKILLCOURT system. Performance was correlated to motor (sprint, jump), cognitive (executive functions, attention, reaction speed) and football specific tests (Loughborough soccer passing test (LSPT)) as well as indirect game metrics (coaches' rating, playing time). Reactive agility performance showed moderate correlations to attention and choice reaction times (r = 0.48−0.63), as well as to the LSPT (r = 0.51). The dual-task agility test revealed moderate relationships with attention and reaction speed (r = 0.47−0.58), executive functions (r = 0.45−0.63), as well as the game metrics (r = 0.51−0.61). Finally, the dual-task agility test significantly differentiated players based on their coaches' rating and playing time using a median split (p < 0.05; d = 0.8–1.28). Motor–cognitive agility performance in elite youth football players seems to be primarily determined by cognitive functions. The integration of multiple object tracking into reactive agility testing seems to be an ecologically valid approach for performance diagnostics in youth football. Highlights * The study introduces a novel motor–cognitive dual-task agility approach (incorporation of multiple-object-tracking in agility testing), evaluating its criterion and ecological validity in elite youth football players compared to a standard agility test. * The standard agility test was shown to have moderate correlations with attention and choice reaction times, while the dual-task agility approach additionally incorporates executive functions * While the agility test correlates to football-specific test performance, the dual-task agility test significantly discriminates players based on their potential ratings and in-season playing time, highlighting its potential as a valuable tool for assessing performance in youth football. * The findings suggest that agility performance in elite youth football is primarily determined by cognitive functions * Incorporating more complex cognitive elements such as multiple-object-tracking in agility testing may improve ecological validity and therefore the predictive value of the testing procedure.