Accuracy of GPS Devices for Measuring High-intensity Running in Field-based Team Sports

Abstract

We compared the accuracy of 2 GPS systems with different sampling rates for the determination of distances covered at high-speed and metabolic power derived from a combination of running speed and acceleration. 8 participants performed 56 bouts of shuttle intermittent running wearing 2 portable GPS devices (SPI-Pro, GPS-5?Hz and MinimaxX, GPS-10?Hz). The GPS systems were compared with a radar system as a criterion measure. The variables investigated were: total distance (TD), high-speed distance (HSR>4.17?m?s?1), very high-speed distance (VHSR>5.56?m?s?1), mean power (Pmean), high metabolic power (HMP>20?W?kg?1) and very high metabolic power (VHMP>25?W?kg?1). GPS-5?Hz had low error for TD (2.8%) and Pmean (4.5%), while the errors for the other variables ranged from moderate to high (7.5?23.2%). GPS-10?Hz demonstrated a low error for TD (1.9%), HSR (4.7%), Pmean (2.4%) and HMP (4.5%), whereas the errors for VHSR (10.5%) and VHMP (6.2%) were moderate. In general, GPS accuracy increased with a higher sampling rate, but decreased with increasing speed of movement. Both systems could be used for calculating TD and Pmean, but they cannot be used interchangeably. Only GPS-10?Hz demonstrated a sufficient level of accuracy for quantifying distance covered at higher speeds or time spent at very high power.

Physical Demands of Representative Match-Play in Adolescent Rugby Union

“…The 10 Hz GPS units used in this study have previously been shown to be more reliable than 5 and 15 Hz GPS (25,36). The GPS units used have a typical error (expressed as coefficient of variation; CV) of 1.9, 4.7 and 10.5% for total distance, high-speed running (>4.7 m.s -1 ) and very high-speed running (>5.56 m.s -1 ), respectively (36).…”

“…The GPS units used have a typical error (expressed as coefficient of variation; CV) of 1.9, 4.7 and 10.5% for total distance, high-speed running (>4.7 m.s -1 ) and very high-speed running (>5.56 m.s -1 ), respectively (36). The accelerometer in the unit has also been shown to have an acceptable CV for within (0.91-1.05%) and between (1.02-1.10%) unit reliability (3).…”

The reliability of the submaximal version of the Yo-Yo intermittent recovery test in elite youth soccer

“…These systems have been shown to collect valid and reliable data. 21 The Yo-Yo IR1-sub was terminated after 6 min at 14.5 km.hr -1 with a total distance of 720 m completed. Heart rate at this time point was recorded (HR6).…”

Establishing a duration standard for the calculation of session rating of perceived exertion in NCAA division I men’s soccer

“…The device has been reported to be both reliable and valid in previous studies. 10,12 The team completed four to seven sessions per week, with a mean of 75.1 ± 23.5 minutes played per match and training session duration of 68.5 ± 17.3 minutes. All of the observed training sessions were designed by the team's head coach and sport scientist.…”

“…GPS technology has improved over the last several years 9 and evidence indicates that GPS data can provide a viable estimate of external training loads imposed on athletes in team sports. [10][11][12] In order to improve measurements of change-of-direction and contact activities, GPS units have been equipped with additional gyroscope and triaxial accelerometer technology. 13 The information provided from GPS is much more objective compared to session RPE.…”