<p>This study investigated how stimulus material and effector specificity influence interference control (a form of inhibitory control) in adolescent players. Ninety-one males aged 15–18 years (28 handball players, 34 soccer players, 29 non-player controls) completed nine modified Flanker task versions varying in stimulus type (abstract, handball-specific, soccer-specific) and response modality (finger, hand, foot). Mixed-design ANOVAs revealed significant main effects of congruency, stimulus type, and response modality. Responses were slower, and interference effects were larger in incongruent than in congruent trials. In addition, sports-specific stimuli and more motorically demanding response modalities were associated with increased response times compared to abstract arrow stimuli and simple finger responses. A congruency × stimulus interaction revealed reduced flanker effects for sports-specific stimuli, indicating that domain-specificity shapes interference processing. However, no consistent group differences were found, suggesting adolescent players do not exhibit broad cognitive advantages, or such advantages are context-dependent. Overall, the findings suggest that performance was primarily shaped by perceptual and motor requirements of the task, i.e., bystimulus complexity and response modality rather than by differences between athlete and control groups. Longitudinal research is needed to clarify how training and development interact to shape cognitive–motor control.</p>