Abstract
Use of the Global Positioning System (GPS) for quantifying athletic performance is common in many team sports. The effect of running velocity on measurement validity is well established, but the influence of rapid directional change is not well understood in team sport applications. This effect was systematically evaluated using multidirectional and curvilinear adaptations of a validated soccer simulation protocol that maintained identical velocity profiles. Team sport athletes completed 90 min trials of the Loughborough Intermittent Shuttle-running Test movement pattern on curvilinear, and multidirectional shuttle running tracks while wearing a 5 Hz (with interpolated 15 Hz output) GPS device. Reference total distance (13 200 m) was systematically over- and underestimated during curvilinear (2.61±0.80%) and shuttle (−3.17±2.46%) trials, respectively. Within-epoch measurement uncertainty dispersion was widest during the shuttle trial, particularly during the jog and run phases. Relative measurement reliability was excellent during both trials (Curvilinear r = 1.00, slope = 1.03, ICC = 1.00; Shuttle r = 0.99, slope = 0.97, ICC = 0.99). Absolute measurement reliability was superior during the curvilinear trial (Curvilinear SEM = 0 m, CV = 2.16%, LOA ± 223 m; Shuttle SEM = 119 m, CV = 2.44%, LOA ± 453 m). Rapid directional change degrades the accuracy and absolute reliability of GPS distance measurement, and caution is recommended when using GPS to quantify rapid multidirectional movement patterns.
Highlights
Use of Global Positioning System (GPS) technology as a performance analysis tool is increasingly common in a number of team sports [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
The systematic positive bias between GPS and reference distances during the curvilinear trial is consistent with previous investigations employing running protocols with low directional demands [18,24]
The negative distance measurement bias during the shuttle trial is consistent with uncertainties reported during simulated court sports, team sports and non-linear running [18,33]; positive biases have been reported during field hockey and team sport simulations [16,25]
Summary
Use of Global Positioning System (GPS) technology as a performance analysis tool is increasingly common in a number of team sports [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]. Despite considerable variation in experimental design previous investigations report small relative distance and velocity measurement uncertainties, and prevailing conclusions support the use of GPS devices during team sport activities [16,17,18,19,20,21,22,23,24,25]. While GPS devices appear acceptably valid for quantifying performance across entire bouts of exercise, sport scientists, coaches and governing bodies have shown particular interest in quantifying the high intensity activity demands of match-play [6,7,10,26,27]. It appears likely that GPS devices underestimate some movement patterns that are of critical importance during training and match-play
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
