Validation of electronic performance and tracking systems EPTS under field conditions

Area of Science:

• Sports Science
• Biomechanics
• Performance Analysis

Background:

• Accurate athlete tracking is crucial for performance analysis in professional team sports.
• Multiple technologies, including video-based systems (VID), local positioning systems (LPS), and global positioning systems (GPS), are commonly employed.
• Understanding the validity and limitations of each technology is essential for reliable data interpretation.

Purpose of the Study:

• To assess and compare the measurement accuracy of VID, LPS, and GPS technologies.
• To quantify the root mean square error (RMSE) for position, speed, and acceleration measures against a reference system.
• To evaluate the validity of these tracking technologies in a sport-specific context.

Main Methods:

• Fourteen male U19 soccer players participated in the study.
• A VICON motion capture system served as the reference for simultaneous data recording.
• Test protocols included a sport-specific course, shuttle runs, and small-sided games on an outdoor field.

Main Results:

• Local positioning systems (LPS) demonstrated superior accuracy in measuring athlete position (23±7 cm) compared to VID (56±16 cm) and GPS (96±49 cm).
• GPS (0.28±0.07 m·s⁻¹) and LPS (0.25±0.06 m·s⁻¹) showed lower errors in speed measures than VID (0.41±0.08 m·s⁻¹).
• Errors increased with object speed, with over 40% deviation from the reference system for high-speed distance measures across all technologies.

Conclusions:

• Significant differences exist in the validity of tracking data between VID, LPS, and GPS technologies.
• LPS offers the highest accuracy for position tracking, while GPS and LPS are more reliable for speed and acceleration.
• Comparisons of performance data across different tracking systems should be made with caution due to inherent accuracy variations.