Adapting U-13 Basketball Competition Based on Maturity Stage to Create Healthy Practice Environments

Purpose : The aim of the present study is to analyze the impact of rule modifications in competition on heart rate and heart rate variability in U-13 basketball players, considering maturity stage as a moderating variable. Method : Forty basketball players with an average age of 12.91 (0.57) years participated in the study. The study was approved by the ethics committee of the University of Murcia (2828/2020). A quasi-experimental A-B study was designed, where A was a tournament with the FEB regulation and B a tournament with the modified regulation. The dependent variables analyzed were the time players spent in different heart rate zones and heart rate variability. Maturity stage was considered a moderating factor in the intervention effect. Results : The results show significant differences in time in zone 4, reduced time in zone 5, maximum heart rate, and square root of the mean value of the sum of the squared differences. Maturity stage conditioned the intervention effect for square root of the mean value of the sum of the squared differences when players had a percentage of predicted adult height higher than 89.92%. Conclusion : From a cardio protective perspective, it has been found that U-13 players spend more time in zones considered cardio protective during the modified tournament. In addition, the modification reduces the differences in terms of fatigue between early and late developing players.