Physical and technical performance of elite youth soccer players during international tournaments: influence of playing position and team success and opponent quality

This study investigated the positional differences in physical performance of elite youth footballers in a tournament scenario and the influence of team success and opponent quality on team physical and technical performance. Match performance observations were collected using a semi-automated multi-camera tracking system across 2 elite under-17 international club tournaments from all players and teams (n = 1,457 individual cases). Teams were classified based on their final tournament ranking as top (1-4 ranking), middle (5-8 ranking) and bottom (9-12 ranking). Technical performance measures were expressed in absolute terms and relative to the time the team was in ball possession. Positional differences in physical performance and the influence of team success and opponent quality on team match performance were identified using a generalised linear mixed model. Positional differences were similar to that observed in elite senior players. Top ranking teams performed a greater number of absolute and relative shots and shots on target than bottom teams (effect size = 0.67-0.82). Top ranking teams performed a greater number of relative tackles than bottom and middle teams (ES; 0.44 -0.70). When playing against top ranking opponents the number of absolute shots and shots on target, shot conversion and passing accuracy were lowest compared with playing against middle and bottom opponents (ES; -0.86 to -0.31). In an elite youth tournament setting, opponent quality and team success can influence match performance. These contextual factors should be considered when analysing match performance and used to inform team tactics, selection and substitution strategies.