An automatic tracking analysis of the movement velocities of national level basketball guards, forwards and centres.

Introduction. Knowledge of the physical demands undertaken by basketball players during the match can help coaches to develop appropriate training regimes and optimise players'performances. A notational analysis has been assessed on many occasions to evaluate a player's activity profiles for different types of player. Conse- quently, movement patterns were not described in physical units. The aim of this study is to analyse players' movement intensities in respect to different velocity classes and to distinguish differences between diferent types of players by using computer-vision technology. Methods. 15 players were recorded with two video cameras fastened to the ceiling. Digital images were proc- essed by the SAGIT tracking system and movement intensity was classified into 4 different velocity categories (walking, slow run, fast run and sprint). The percentage of time players spent in each velocity class was as- sessed using a three way repeated measures ANOVA. Results. The two way interactions between velocity class and quarter (F = 2.34, df = 9, 405; p < 0.05) and velocity class and position (F = 11.64, df = 6, 405; p < 0.001) suggested that the different playing positions undertook different amounts of work and these were influenced by the period of the game in which they were playing. Specifically the amount of time spent in slower movement classes tended to greater during the earlier time periods and as time progressed the amount of time spent in faster movement categories decreased. Conclusion. These results suggest that further work is needed to assess the practical application of the findings. For example, to what extent does a player's velocity relate to the different role being undertaken. For example when players gain possession of the ball as the play transits from defence to offence are the highest velocities reached? Therefore, we need to explore movement patterns in defence, offence and during transitions.

Research paper presented at the International Scientific Conference of theoretical, methodological and methodical aspects of competition and athletes’ preparation, Belgrade, Serbia, December 2009.