Universidad Europea de Madrid, Faculty of Sport Sciences, Villaviciosa de Odón, 28670 Madrid, Spain.
Universidad de Castilla-La Mancha, IGOID Research Group, 45071 Toledo, Spain.
Sensors (Basel). 2019 Sep 23;19(19):4113. doi: 10.3390/s19194113.
The aim of the present study was to assess the accuracy of a multi-camera tracking system (Mediacoach) to track elite football players' movements in real time. A total of 207 observations of 38 official matches from Liga 1, 2, 3™ (2nd Spanish Division, season 2017/18) were included in the study (88 defenders, 84 midfielders, and 35 attackers of the same team). Total distance (TD, m) distance in zone 4 (DZ4) at a speed of 14-21 km/h, distance in zone 5 (DZ5) at a speed of 21-24 km/h (DZ5), distance in zone 6 (DZ6) at a speed of ≥24 km/h, maximum speed (km/h), and number of sprints (actions above 24 km/h) were registered with the Apex GPS system (STATSports™, Newry, N. Ireland) and Mediacoach semi-automatic tracking system (LaLiga™, Madrid, Spain). The level of agreement between variables estimated by the two systems was analyzed. Bias was also calculated by deducting the GPS estimated value from the video estimated value, and then dividing the difference score by the GPS estimated value. All variables showed high ICC values (>0.75) and very large correlations (r > 0.70). However the video-based performance analysis system overestimated the results obtained in the different speed zones (DZ5: +16.59 ± 62.29 m; LOA95%: -105.49 to 138.68; DZ6: +93.26 ± 67.76 m; LOA95%: -39.55 to 226.07), the number of sprints (+2.27 ± 2.94; LOA95%: -3.49 to 8.02), and the maximum speed (+0.32 ± 1.25 km/h; LOA95%: -2.13 to 2.77). The maximum bias was found in DZ6 (47%). This demonstrates that Mediacoach is as accurate as a GPS system to obtain objective data in real time, adapted to physical and movement demands of elite football, especially for total distance and distances traveled at medium speeds.
本研究旨在评估多摄像机跟踪系统（Mediacoach）实时跟踪精英足球运动员运动的准确性。该研究共纳入 38 场来自 Liga 1、2、3（西班牙乙级联赛，2017/18 赛季）的正式比赛的 207 次观察结果（同一球队的 88 名后卫、84 名中场和 35 名前锋）。使用 Apex GPS 系统（STATSports™，Newry，北爱尔兰）和 Mediacoach 半自动跟踪系统（LaLiga™，马德里，西班牙）记录总距离（TD，m）在 14-21km/h 速度下的区域 4（DZ4）的距离、在 21-24km/h（DZ5）速度下的区域 5（DZ5）的距离、在速度≥24km/h 的区域 6（DZ6）的距离、最大速度（km/h）和冲刺次数（速度大于 24km/h 的动作）。分析了两个系统估计的变量之间的一致性水平。还通过从视频估计值中减去 GPS 估计值来计算偏差，然后将差值除以 GPS 估计值。所有变量的 ICC 值均>0.75，且相关性非常高（r>0.70）。然而，基于视频的表现分析系统高估了不同速度区（DZ5：+16.59±62.29m；LOA95%：-105.49 至 138.68；DZ6：+93.26±67.76m；LOA95%：-39.55 至 226.07）、冲刺次数（+2.27±2.94；LOA95%：-3.49 至 8.02）和最大速度（+0.32±1.25km/h；LOA95%：-2.13 至 2.77）的结果。最大偏差出现在 DZ6（47%）。这表明 Mediacoach 与 GPS 系统一样准确，可实时获取客观数据，适用于精英足球的身体和运动需求，尤其是总距离和中速行驶距离。
