VIREF: REVISTA DE EDUCACIÓN FÍSICA, cilt.9, ss.48-74, 2020 (ESCI İndekslerine Giren Dergi)
Objective: the purpose of this study was to examine the effects of mental toughness and decision-making styles on the competition performances of footballer candidates who were receiving infrastructure training in professional football teams. Method: the population of the study consisted of a total of 48 footballer candidates playing in the U19 team of the Kayseri Sports Club. The sample group consisted of 24 volunteers, who were footballer candidates in the Kayserispor U19 team. To collect the information, a socio-demographic information form, a mental toughness scale and the Turkish validity and reliability study, and the Melbourne decision-making scale, adapted into Turkey, were used. The experimental group received mental toughness and decision-making styles training five times a day for four weeks. The daily training consisted of two 40 minutes sessions. For the analysis of the competition played by the athletes of the experimental group, a computer with MacOS and 5K screen support and the E Analysis Soccer Project football match analysis system were used. The obtained data were recorded with the IBM SPSS 20 package program. Independent Sample T-test was used to reveal the difference between the in-group pre-test, mid-test and post-test data of the scales and competition analyzes, and Repeated Measures ANOVA were used to determine the effect of the training provided. The one-way ANOVA test was used for the pre-test, mid-test and post-test comparisons of the results obtained from the competition analyzes, while LSD test was used to determine which tests showed significant differences. Results: as a result, it was concluded that the 4-week mental toughness and decision-making style training affected the performance of the footballer candidates, who were receiving infrastructure training in professional football teams and positively affected the competition performance of the players.