@article { , title = {The use of individualized speed and intensity thresholds for determining the distance run at high-intensity in professional soccer}, abstract = {As with other match analysis systems, ProZone® uses an absolute speed threshold to identify running speeds at "high-intensity". In this study, we examined the use of an individualized high-intensity speed threshold based on the speed at the second ventilatory threshold (VT 2speed ) for assessment of the distance run at high-intensity during matches. Ten professional soccer players completed a maximal treadmill test to determine VT 2speed . Match data were identified by means of the ProZone® match analysis system. The distances run at high-intensity during matches were calculated using the default value (19.8 km·h -1 ) and VT 2speed . Differences between VT 2speed and the default were analysed using a non-parametric median sign test. The distances run at high-intensity were compared with a paired t-test. The median VT 2speed was 15 km·h -1 (range 14-16 km·h -1 ), which was less than the default (P < 0.01). Mean distance run at high-intensity based on the default and VT 2speed was 845 m (s = 296) and 2258 m (s = 707), respectively [mean difference 1413 m; P < 0.001 (95\% CI: 1037-1789 m)]. The high-intensity running speeds based on the second ventilatory threshold are substantially less than that used as the default within the ProZone® match analysis system, thus the distance run at high-intensity can be substantially underestimated.}, doi = {10.1080/02640410902998239}, eissn = {1466-447X}, issn = {0264-0414}, issue = {9}, journal = {JOURNAL OF SPORTS SCIENCES}, note = {Batch 003. Output ID 24276.}, pages = {893-898}, publicationstatus = {Published}, publisher = {Taylor and Francis}, url = {https://hull-repository.worktribe.com/output/396000}, volume = {27}, keyword = {Health and Health Inequalities, ProZone, Soccer, Exercise intensity}, year = {2009}, author = {Lovell, Ric and Abt, Grant} }