The influence of youth soccer players' sprint performance on the different sided games' external load using GPS devices.

The aims of this study are 1) to compare sided games' (SGs) external responses encountered by players according to pitch size and to 2) examine the relationships between sprint performance and SGs' external physical responses. Twenty soccer players under 15 years of age (U-15) participated in this study. Each player performed a sprinting test (10 m and 30 m sprints) and played a SG on two different pitch sizes (small at 100 [SSG] and large at 200 [LSG] m2 per player). Higher external responses (p < 0.01, ES = -6.41-1.22) were found in LSG in comparison to SSG, except to distance accelerating and decelerating (p > 0.05, ES = -0.26-0.27). Players who were faster over 10 and 30 m covered higher distances cruising and sprinting (r = -0.47/-0.66; ± 0.23/± 0.30, respectively, p < 0.05), performed a greater number of sprints, achieved higher maximum velocity (Velmax) during LSG and covered a greater distance at high-intensity accelerating (r = -0.50/-0.70; ±0.21/±0.29, respectively, p < 0.05) during both SG. LSG demanded a higher external load in comparison with SSG. In addition, the improved sprint capacity could allow players to perform greater running activities and short-term actions at high-intensities during SG.