The Relative Age Effect of Male and Female Japanese National Soccer Players

Abstract

The relative age effect (RAE) of Japanese national soccer players has not been examined to date. The purpose of this study was to examine the RAE of male and female Japanese national soccer players, targeting players who were called up to the Japanese national team from 2014 to 2020. The subjects were 241 national soccer players (143 male and 98 female). Even if they were called up to national team more than once, they were counted as one person. Among the Japanese male national soccer players, Q1 (January to March) was 31.5%, Q2 (April to June) was 22.4%, Q3 (July to September) was 20.3%, and Q4 (October to December) was 25.9%. As a result of the goodness-of-fit test, no significant difference was observed in the proportions of Q1 to Q4. Q1/Q4 was 1.22, and S1/S2 was 1.17. Among female national soccer players, Q1, Q2, Q3, and Q4 were 20.4%, 28.6%, 27.6%, and 23.5% respectively. No significant difference was observed in the proportions of Q1 to Q4. Q1/Q4 was 0.87, and S1/S2 was 0.96. We concluded that there is no RAE for Japanese national soccer players, whether men or women. Since the number of subjects is insufficient, it will be necessary to return to the analysis of the RAE of Japanese national soccer players in the future.