Does sprint and jump performance of football players from a Premier League academy change throughout the season?

Purpose The aim of this study was to investigate the sprint and jump performance throughout the season in young male players aged 13-18 years from a Premier League football (soccer) academy.Methods Participants were engaged in a 6-day weekly football training routine. Plyometric and sprint exercises were embedded in training sessions but did not follow a systematized program. Performance on 10-m and 30-m sprints, vertical and horizontal jumps were assessed at the beginning, middle, and end of competitive calendar along two consecutive seasons. This retrospective longitudinal study analyzed 94 players from under-14 to under-19 teams (56 players in both seasons and 38 in a single season; i.e., 150 player-seasons).Results Players had significant performance improvements along the season: 10-m sprint [p < 0.001, delta = - 0.06 s (- 2.93%), effect size (ES) = 0.60], 30-m sprint [p < 0.001, delta = - 0.11 s (- 2.46%), ES = 0.54], vertical jump [p = 0.005, delta = 1.84 cm (5.45%), ES = 0.37], and horizontal jump [p = 0.005, delta = 6.48 cm (2.86%), ES = 0.37]. Individual analyses on age categories denoted that significant performance improvements mostly occurred in under-14, under-15, and under-16 teams. Under-18 and under-19 teams had no significant increases in any performance test, while under-17 team had an increase only in the 30-m sprint test.Conclusion Regular football training routine (without systematized plyometric or sprint training) was able to enhance sprint and jump performance of footballers from under-14 to under-16 teams, but this training regime was insufficient to improve such abilities of older players (under-17 to under-19 teams).