Simultaneous performance of a perceptual-cognitive and a motor task is performance-relevant in interactive sports and is measured via cognitive-motor dual-task (DT) paradigms under time pressure. This typically leads to performance decrements compared to single task performance (ST) (costs; Moreira et al., 2021). We focused on motor costs to analyze possible underlying factors (e.g., gender, cognitive performance). As part of the in:prove project, 117 elite athletes (female = 55) completed a speed cognitive-motor DT. Maximal tapping frequency (i.e., alternating foot contacts) and Stroop performance were assessed under ST and DT. Furthermore, cognitive performance (e.g., processing speed, working memory) was measured. For tapping frequency, a 2 x 2 ANOVA (‘condition’; ‘gender’), for motor costs, a multiple linear regression with all variables were calculated. Results indicate main effects for ‘condition’ (F(1,115) = 233.75, p < .001, ηp² = .67) with higher tapping frequency in ST as well as for male athletes (F(1,115) = 27.94, p < .001, ηp² = .20). Notably, an interaction effect emerges (F(1,115) = 4.16, p = .044, ηp² = .035), with females showing greater reduction in tapping frequency under DT. Multiple linear regression indicates ‘gender’ (β = .28, p = .060) and ‘Stroop performance’ (β = .40, p = .011) as predictors of motor costs (F(3,45) = 3.38, p = .026, adjusted R² = .13), but not ‘cognitive performance’. This suggests that motor costs in speed tasks are higher in females and in individuals with lower Stroop performance – the latter primarily driven by female athletes.