Characterization and Comparison of Athletic Performance and Change of Direction Deficit Across Youth Futsal Age Groups

<b>Background/Objectives:</b> Futsal players need peak strength, functional capacity, speed, and explosive lower-limb power for optimal performance. The aim of this study was to (i) characterize and compare anthropometric characteristics, lower limb strength/power, dynamic balance, linear sprint speed, COD performance, and COD deficit across young futsal age groups and (ii) identify key predictors of COD deficit. <b>Methods</b>: Thirty-three male futsal players from three age groups (U13, U15, and U17) were tested. <b>Results</b>: All anthropometric variables showed significant group effects with moderate to strong effect sizes, where U17 presented the largest values, followed by U15 and U13. Strength and power variables presented the same trend. The dynamic balance differed significantly across groups. Significant differences between groups with moderate effect sizes were noted in linear sprints (F = 19.54, <i>p</i> < 0.001, η² = 0.57), zigzag (F = 19.54, <i>p</i> = 0.002, η² = 0.35), and COD deficit (F = 19.54, <i>p</i> < 0.001, η² = 0.46). Post hoc tests revealed that U13 and U15 outperformed U17 in the COD deficit (<i>p</i> < 0.002). The COD deficit showed a quadratic relationship with age, initially improving but later declining in older players (<i>p</i> < 0.001). The body mass and the posteromedial relative difference predicted the COD deficit, with the coefficient of determination (R²) explaining 39% of the COD variance. <b>Conclusions</b>: Coaches and practitioners should utilize COD drills to target various movement patterns and account for pubertal timing, as growth can impact performance.