TY  - JOUR
PY  - 2018//
TI  - The use of relative speed zones in Australian football: are we really measuring what we think we are?
JO  - International journal of sports physiology and performance
A1  - Murray, Nick B.
A1  - Gabbett, Tim J.
A1  - Townshend, Andrew D.
SP  - 442
EP  - 451
VL  - 13
IS  - 4
N2  - OBJECTIVES: This study aimed to examine the difference between absolute and relative workloads, injury likelihood, and the acute:chronic workload ratio (ACWR) in elite Australian football. <br><br>DESIGN: Single cohort, observational study. <br><br>METHODS: Forty-five elite Australian football players from one club participated in this study. Running workloads of players were tracked using Global Positioning System technology, and were categorised using either; (1) absolute, pre-defined speed thresholds, or (2) relative, individualised speed thresholds. Players were divided into three equal groups based on maximum velocity; (1) faster, (2) moderate, or (3) slower. One-week and four-week workloads were calculated, along with the ACWR. Injuries were recorded if they were non-contact in nature and resulted in "time-loss". <br><br>RESULTS: Faster players demonstrated a significant overestimation of very high-speed running when compared to their relative thresholds (p=0.01, ES=-0.73). Similarly, slower players demonstrated an underestimation of high- (p=0.06, ES=0.55) and very high-speed (p=0.01, ES=1.16) running when compared to their relative thresholds. For slower players, (1) greater amounts of relative very high-speed running had a greater risk of injury than less (RR=8.30, p=0.04), and (2) greater absolute high-speed chronic workloads demonstrated an increase in injury likelihood (RR=2.28, p=0.16), while greater relative high-speed chronic workloads offered a decrease in injury likelihood (RR=0.33, p=0.11). Faster players with a very high-speed ACWR of >2.0 had a greater risk of injury than those between 0.49-0.99 for both absolute (RR=10.31, p=0.09) and relative (RR=4.28, p=0.13) workloads. <br><br>CONCLUSIONS: The individualisation of velocity thresholds significantly alters the amount of very high-speed running performed and should be considered in the prescription of training load.<p />  <p>Language: en</p>
LA  - en
SN  - 1555-0265
UR  - http://dx.doi.org/10.1123/ijspp.2017-0148
ID  - ref1
ER  -