Effect of Rule Changes on Performance Parameters for Women's Water Polo Over Three Seasons

Water polo’s rule changes are proposed to improve performance throw a faster game with more goals, less wrestling and more technical skills. The rule changes may modify the players' perception and game actions. However, there are some critical differences between male and female water polo teams. To date, we have not found any study about female water polo rule changes effects over the seasons. This study aimed to verify the effects of water polo rule changes on the performance of female elite-level teams over the three seasons. The data were collected through official game reports from the European water polo league for female tournaments, totaling 63 matches. Goals, goals per quarter, exclusion fouls, and penalty fouls were registered and analyzed. Mean, standard deviation, and 95% confidence intervals were calculated for all variables. Generalized estimating equations were applied to compare the variables in the three moments. Effect sizes (Cohen's d) were calculated. SPSS 20.0 was used in all analyses. The alpha significance level was established at 0.05. No statistical differences were found over seasons' post-water polo rule changes for goals, goals per quarter, exclusion fouls, and penalty fouls variables, and the effect sizes were just from trivial to small. The 2019 and 2021 water polo rule changes do not provoke statistical effects in female water polo teams over the 2019/2020, 2021/2022 and 2022/2023 seasons.