ABSTRACT
Due to technological developments and permission from federations such as FIFA, radio-frequency based technology (i.e. Global Positioning Systems (GPS) or Global Navigation Satellite Systems (GNSS) and Local Positioning Systems (LPS)) has become popular in team sports. Today, real-time feedback is available due to the development of WBAN (Wireless Body Area Networks) in data transmission possibilities from devices to the PC, tablet or mobile, where the data are shown, offering a competitive advantage for team sports. However, there is debate about the accuracy of real-time data versus data downloaded after a session. It has been found that whilst the signal exceeded the noise for real time collection for total distance, this was considerably reduced during lower intensity efforts (smaller meaningful distance [SMD]) for jogging (4.2 to 5.0 m∙s−1) = 33.5 m; running (5.0 to 6.9 m∙s−1) = 31.9 m; sprinting = 17.3 m). Similarly, post-session PlayerLoad™ data have been found to be both reliable and valid in real-time using microelectromechanical systems (MEMS), while moderate errors were found when compared to the data downloaded directly from the device. Therefore, it seems that real-time feedback will be a valuable tool for sports technicians. However, although there has been great development in real-time feedback, manufacturers should further develop their systems to guarantee high quality measures.
