Validity and reliability of a player-tracking device to identify movement orientation in team sports

The purpose of this study was to determine the validity and reliability of the GPExe pro2 device to identify movement orientation in team-sport locomotion. Part A involved a series of discrete movement tasks of varying direction and orientation at two speeds (walk, run); Part B involved a continuous Simulated Game Circuit (SGC). For validity, distance in each orientation quadrant (forward, backward, left, right) and two aggregated sectors (lateral, non-forward), was compared to the known distance and calculated as the standard error of estimate (SEE). Inter-unit reliability was assessed in the SGC and reported as typical error (TE) and coefficient of variation (CV). In total, 256 trials were collected for validity (Part A 232, Part B 24), and 17 trials for reliability. Validity improved with faster and more continuous movement (SEE: walk 6.2–8.7%; run 4.4–8.2%; SGC 1.0–6.2%), was better for forward and backward (1.0–2.8%) compared to left and right orientation (3.8–6.2%), and for aggregated sectors (2.4–5.1%) rather than specific quadrants. Reliability was good (CV<5%) for forward and backward quadrants and both aggregated sectors, but poor (CV>10%) for left and right quadrants. These devices provide valid and reliable movement orientation data for team-sport locomotion, particularly in differentiating between forward and non-forward movement.