The influence of match-induced fatigue on sprint ability and technique of change of direction in soccer players: A pilot study

Evidence regarding fatigue effects on change of direction (COD) technique is scarce. Study aims: 1) to investigate the effects of fatigue during different periods of a youth soccer match on players’ 15 m linear sprint (15LS) with 10 m split-time, 15 m COD, and COD technique; 2) to assess these performances 72-h post-match. Ten young male soccer players (age = 16 ± 0.57 yr, body mass = 66.41 ± 6.48 kg, height = 177.7 ± 6.73 cm) participated in this study. Tests were organized as follows:1) standardized warm-up; 2) pre-match (15LS and 15COD); 3) P1-20’ (15COD and RPE); 4) P2-40’ (15LS, 15COD, RPE); 5) P3-60’ (15COD, RPE); 6) P4-80’ (15LS, 15COD, RPE) and 72-h post-match (15LS, 15COD). COD executions were analyzed using Kinovea. No significant match-induced fatigue effect (p > 0.05) was observed for 15LS or 10 m split times. The 15COD test showed significant effects at various match time points (p < 0.01). Post-hoc analysis showed no differences between PRE and P1 (p > 0.05), while P2, P3 and P4 were significantly different from PRE and P1 (p < 0.001), with partial eta squared value of (η2 = 0.76). POST showed significant differences with P2, P3, and P4 (p < 0.05). Players’ COD technique shifted from sharp to rounded executions, with sharp dominant pre-match. Significant differences (p < 0.05) in RPE and session-RPE indicated increased load as the match progressed. In conclusion, COD performance declined during and after the match, primarily due to fatigue, which affects it more than linear sprinting.