Seasonal changes and variability of physical match demands in a highly trained female soccer team

This work aimed to identify the sources of variability in match physical performance of highly trained female soccer players and quantify individual between-match changes in global positioning systems (GPS) derived metrics. Official match data belonging to 27 players across two competitive seasons was analyzed, resulting in 344 individual observations. GPS metrics included total distance covered (TD), distance covered per min, high-speed running distance covered (HSRD, 19.8-25.2 km/h), high-metabolic load distance (HMLD, > 20 W/kg), maximal speed (Max speed (km/h)), and high-intensity accelerations and decelerations distances covered (> 2.5 m/s^-2). Seasonal variation trends and variability across players, positions, and matches were quantified using linear mixed models. Reference values for interpreting between-match changes were established based on observed match-to-match variability and the smallest worthwhile changes. Results indicated that lower-intensity metrics such as TD, m/min, and max speed were relatively stable, with a minimum detectable change of approximately ± 14%. In contrast, high-intensity metrics such as HSRD, HMLD, and acceleration/deceleration distances demonstrated greater variability, requiring changes > 30% to exceed expected fluctuations. Considering the cohort of the study, findings suggest that high-intensity metrics present the highest variability and, consequently, considerably higher minimum detectable change thresholds. Practitioners may consider the variability thresholds presented when interpreting match-to-match changes and individualizing player monitoring strategies.