INTRODUCTION: Many studies have been published being interested in the meas-urement of velocity of balls, implements and corporal segments in sports where those skills are basic for performance. Skill in passing and throwing is vital in Water Polo because accuracy and the ability to produce high velocities are also valuable during the game for shots at goal. The aim of the present study was twofold; firstly to evaluate the validity of the radar measurements versus high velocity 2D photogrammetric analysis, in two different situation, and secondly, to establish a valid methodology to asses throwing velocity in Water Polo. METHODS: The participants carried out 48 throws at maximum intensity from the penalty position (24 throws), and from an oblique position to the goal (¥è ~ 20¨¬) in the same penalty line (24 throws) with and without goal-keeper. They executed throws by alternating manner with a 3-min rest between each. The ball maximum velocity was measured with radar placed ten meters behind the goal, and aligned with the penalty line. Simultaneously; a 2D photogrammetric study was accomplished. The camera was mounted on a rigid tripod at a height of 1.0 m and placed at a distance of 10 m from the middle of the athlete¡¯s lane. The optical axis of the camera was perpendicular to the direction of throwing for each different situation. One trial by each participant for each throw condition was analyzed. After the throws were analyzed, Pearson correlation coefficients (SPSS 15.0) were used to determine the interrelationship among the maximum velocity obtained by the radar gun and the 2D analysis. The alpha level was set to p ¡Â 0.05. RESULTS: For frontal throws with-out goalkeeper the ICC was 0.96, and with goalkeeper was 0.84. If we analyze throws in oblique situation (¥á ~ 20¨¬), the ICC was 0.94 without goalkeeper and 0.96 with goalkeeper. When we analyzed all throws in frontal situation the Pearson correlation coefficient obtained was 0.91 and in oblique position was 0.94. In all situations p value was ¡Â 0.001. CONCLUSION: Radar is a valid method to measure throwing velocity in Water Polo, so for frontal throws as well for oblique throws.
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