BASIC THEORETICAL PREMISES AND CALCULATIONS OF OPTIMAL REACH


By Zoran Kačić

The correct choice of a place and position of a goalkeeper in goals is an important precondition for successful saves. Theoretically, the goalkeeper should at any moment be positioned symmetrically, that is on the line which halves the angle, formed by the lines connecting the two goal posts and the ball. He then decides to make an appropriate technical intervention to successfully stop the shot. 

1. Total area coverage area between 1.29m to 1.39m for a shoot from 5m to 7m is achieved by a short and fast lateral jump of maximum length between 1.35m and 1.40m (highlighted column) when the goalkeeper is positioned 0.5m to 0.7m from the goal line.

2. Total area coverage of 1.29m for a shoot from 5m is achieved by goalkeeper’s vertical jump with outstrecthed arms and a short and fast lateral move, thus reac- hing the length between 1.15m and 1.20m (lightly highlighted cells) if the goal- keeper is positioned 0.7m from the goal line. We assume that because of the ball’s diameter of 22cm there is not enough free space for it to pass through.

3. A long, slower lateral jump, from 1.55m to 1.60m is not needed at all.  

4. The goalkeeper’s move from 0.5m to 0.7m forward from the goal line directly, but not greatly, affects the reduction of the length needed for area coverage (the gain is from 4cm to 6cm). Therefore we can conclude that goalkeeper’s greater movement forward is not overly needed. The effect is relatively small while at the same time increasing the susceptibility to a lob shot. 

The following generalisations can be formed from the points above: Goalkeeping style and technique should be based and developed on the short and fast lateral jump. The fundamentals of such technique are based on: a) Maximally hard legwork, allowing a more vertical and relatively high ba- sic position of a goalkeeper. b) Very little support on arms and hands (hands are slightly submersed) c) Reaction speed (according to statistical data, a short and fast lateral jump should take between 0.25 and 0.33 of a second, which corresponds to the flight time of a ball, shot from the common shooting distance between 5m and 7m). 


WPC-banner.gif

​All Rights Reserved, Water Polo School 2019