Spin characteristics of short and long services in elite table tennis: Insights from sex-based comparisons

Ball spin is a central tactical element in table tennis, yet its characteristics during elite competition remain unclear. This study aimed to quantify the spin rate and spin direction of services. In total, 1773 services from 30 professional T. League singles matches (2020–2022) were analyzed, involving 13 male and 16 female players. Ball trajectories were reconstructed from multi-camera recordings, and spin was estimated using a validated computer vision-based method. Services were classified as either short or long using a Gaussian mixture model based on the second bounce position. Statistical comparisons evaluated sex differences, spin direction distributions, and associations with service outcomes. Male players generated higher spin rates and spin parameters than female players, indicating greater brushing control of the ball. Across both sexes, side spin and side-back spin were most frequently used, whereas back spin produced significantly lower spin parameters. Spin rate and direction had only minor effects on service outcomes, with a small influence detected in men's short services. These findings provide the first systematic description of service spin characteristics in elite competition and establish a foundation for future analyses.