Is the positioning of defensive players an aspect to consider in soccer transition games?

This study investigated the influence of defensive player positioning on the external and internal loads experienced during small-sided transition games (TGs) and the subsequent effects on sprint and jump performance. Twenty male youth players (age 15.7 ± 0.2 years; height 175.3 ± 7.5 cm; mass 67.1 ± 6.8 kg) completed two 7-min bouts, with 2 minutes of passive recovery, of 2 vs. 2 TGs under three defensive configurations: defenders in front of attackers (TG_Front), behind attackers (TG_Behind), and parallel to attackers (TG_Parallel). During each TG, we recorded total distance covered (DC), distance covered in running (18.0–20.9 km · h⁻¹), highintensity running (21.0–23.9 km · h⁻¹), and sprinting (> 24.0 km · h⁻¹), peak speed, mechanical load, and the number of accelerations and decelerations > 1.0 m · s⁻² and > 2.5 m · s⁻². Ratings of perceived exertion (RPE) were also collected. Sprint (30 m) and countermovement jump (CMJ) tests were administered immediately before and after each session. The results showed that TG_Parallel and TG_Behind elicited significantly greater DC, distances in running, high-intensity running, and sprinting zones, mechanical load, accelerations > 2.5 m · s⁻², and RPE compared to TGFront (p < 0.05). Moreover, TGParallel produced higher DC in high-intensity running, sprinting, mechanical load, and accelerations > 2.5 m · s⁻² than TGBehind (p < 0.05). No TG format induced significant changes in sprint or CMJ performance (pre- vs. post-test, p > 0.05). These findings demonstrate that positioning defenders behind or parallel to attackers increases both external and internal loads across running, high-intensity, and sprinting zones during TGs, without compromising subsequent sprint or jump performance.