Background: The benefit of light-weight shoes for athletic performance has been recognized in both sport and professional environments. However, the biomechanical mechanism by which reduced shoe weight improves athletic performance is unknown. The aim of this study was to determine the effect of basketball shoe weight on performance and corresponding lower-extremity biomechanics for the example of a 10 m sprint start. Methods: For twenty-two male recreational athletes, sprint start (3.7 m) and 10 m sprint performances were quantified from timing lights in three basketball shoe conditions (light=352 g; medium=510 g; heavy=637 g). Ground reaction forces and kinematics and kinetics of the lower-extremity joints during the first sprinting stride were determined using 3D-motion analysis and a force platform. A Support Vector Machine analysis and linear regression were performed to analyze biomechanical differences between the shoe conditions and their association with performance. Results: Average sprint start and 10 m sprint times in the light shoe were significantly reduced compared to the heavy shoe by up to 24 ms (3%) and 32 ms (1.8%), respectively. The reduction in shoe weight led to significantly different ankle joint biomechanics with a 5% increase in peak plantarflexion velocity in the light shoe that was associated with a decrease in sprint start time. Conclusion: Lighter basketball shoes enhance sprint start performance, likely by facilitating faster ankle plantarflexion during the first sprinting stride. This mechanism can promote player performance during important game scenarios and encourages further innovative light-weight shoe concepts not only in sports but also in working environments that require high athletic performance.