More alike than expected? Longitudinal development of physical and mental skills in male youth football players with different playing status at age 19

Despite interest in talent research, limited evidence exists on how future professionals develop relative to peers. This study tracked the development of biological, physical, and mental characteristics in male football players who played at professional, semi-professional, or amateur level by age 19. Forty-four players were followed from age 14 to 19. Assessments included anthropometrics, biological maturity, training volume, maximal oxygen uptake, sprint performance, jump performance, leg press force and power, and intermittent-endurance performance. Mental skills were measured using a 16-item questionnaire targeting task orientation, effort, self-efficacy, and self-optimization. At age 19, players were classified as professional (n = 7), semi-professional (n = 12), or amateur (n = 25). Linear mixed models were used. No significant group differences were found for biological maturity. Both the professional and semi-professional groups outperformed amateurs across physical performance and capacity measures (p < .001–.033), with the semi-professional group recording higher sprint speeds than their peers (p = .049). Leg power was the only physical parameter that developed differently between groups over time (p = .014), with professionals improving more than their peers. For mental skills, semi-professionals scored higher than amateurs in self-optimization (p = .014), with no other differences found between the professional, semi-professional, or amateur players. In conclusion, youth players who reached the professional level by age 19 demonstrated stronger physical, but not mental profiles, than amateurs, yet showed largely similar developmental patterns to their semi-professional peers. Further research with larger sample sizes is required to confirm the findings of this study.