Assessing the agreement between a global navigation satellite system and an optical-tracking system for measuring total, high-speed running, and sprint distances in official soccer matches

Abstract

This study aimed to compare the agreement of total distance (TD), high-speed running (HSR) distance, and sprint distance during 16 official soccer matches between a global navigation satellite system (GNSS) and an optical-tracking system. A total of 24 male soccer players, who are actively participating in the Polish Ekstraklasa professional league, were included in the analysis conducted during official competitions. The players were systematically monitored using Catapult GNSS (10 Hz, S7) and Tracab optical-tracking system (25-Hz, ChyronHego). TD, HSR distance, sprint distance, HSR count (HSRC), and sprint count (SC) were collected. The data were extracted in 5 min epochs. A statistical approach was employed to visually examine the relationship between the systems based on the same measure. Additionally, R2 was utilized as a metric to quantify the proportion of variance accounted for by a variable. To assess agreement, Bland–Altman plots were visually inspected. The data from both systems were compared using the estimates derived from the intraclass correlation (ICC) test and Pearson product–moment correlation. Finally, a paired t-test was employed to compare the measurements obtained from both systems. The interaction between Catapult and Tracab systems revealed an R2 of 0.717 for TD, 0.512 for HSR distance, 0.647 for sprint distance, 0.349 for HSRC, and 0.261 for SC. The ICC values for absolute agreement between the systems were excellent for TD (ICC=0.974) and good for HSR distance (ICC=0.766), sprint distance (ICC=0.822). The ICC values were not good for HSRCs (ICC=0.659) and SCs (ICC=0.640). t-test revealed significant differences between Catapult and Tracab for TD (p<0.001; d = −0.084), HSR distance (p<0.001; d = −0.481), sprint distance (p<0.001; d = −0.513), HSRC (p<0.001; d = −0.558), and SC (p<0.001; d = −0.334). Although both systems present acceptable agreement in TD, they may not be perfectly inter changeable, which sports scientists and coaches must consider when using them