@article{ref1,
title="The within-match patterns of locomotor efficiency during professional soccer match play: implications for injury risk?",
journal="Journal of science and medicine in sport",
year="2015",
author="Barrett, Steve and Midgley, Adrian and Reeves, Matt and Joel, Tom and Franklin, Ed and Heyworth, Rob and Garrett, Andrew and Lovell, Ric",
volume="19",
number="10",
pages="810-815",
abstract="OBJECTIVES: The principle aim of the current study was to examine within-match patterns of locomotor efficiency in professional soccer, determined as the ratio between tri-axial accelerometer data (PlayerLoad™) and locomotor activities. Between match variability and determinants of PlayerLoad™ during match play were also assessed. <br><br>DESIGN: A single cohort, observational study. <br><br>METHODS: Tri-axial accelerometer data (PlayerLoad™) was recorded during 86 competitive soccer matches in 63 English championship players (574 match observations). Accelerometer data accumulated (PlayerLoad Vector Magnitude [PLVM]) from the individual-component planes of PlayerLoad™ (anterior-posterior PlayerLoad™ [PLAP], medial-lateral PlayerLoad™ [PLML] and vertical PlayerLoad™ [PLV]), together with locomotor activity (Total Distance Covered [TDC]) were determined in 15-min segments. Locomotor efficiency was calculated using the ratio of PLVM and TDC (PlayerLoad™ per metre). The proportion of variance explaining the within-match trends in PLVM, PLAP, APML, APv, and TDC was determined owing to matches, individual players, and positional role. <br><br>RESULTS: PLVM, PLAP, APML, APv and TDC reduced after the initial 15-min match period (p=0.001; η(2)=0.22-0.43, large effects). PL:TDC increased in the last 15min of each half (p=0.001; η(2)=0.25, large effect). The variance in PLVM during soccer match-play was explained by individual players (63.9%; p=0.001) and between-match variation (21.6%; p=0.001), but not positional role (14.1%; p=0.364). <br><br>CONCLUSIONS: Locomotor efficiency is lower during the latter stages of each half of competitive soccer match-play, a trend synonymous with observations of increased injury incidence and fatigue in these periods. Locomotor efficiency may be a valuable metric to identify fatigue and heightened injury risk during soccer training and match-play.<p /> <p>Language: en</p>",
language="en",
issn="1440-2440",
doi="10.1016/j.jsams.2015.12.514",
url="http://dx.doi.org/10.1016/j.jsams.2015.12.514"
}