Original Research ARTICLE
The individual and combined effects of multiple factors on the risk of soft tissue non-contact injuries in elite team sport athletes
- 1Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Australia, Australia
Aim: Relationships between athlete monitoring-derived variables and injury risk have been investigated predominantly in isolation. The aim of this study was to evaluate the individual and combined effects of multiple factors on the risk of soft-tissue non-contact injuries in elite team sport athletes. Methods: Fifty-five elite Australian footballers were prospectively monitored over two consecutive seasons. Internal and external training load was quantified using the session rating of perceived exertion and GPS/accelerometry respectively. Cumulative load and acute-to-chronic workload ratios were derived using rolling averages and exponentially weighted moving averages. History of injuries in the current and previous seasons was recorded along with professional experience, weekly musculoskeletal screening, and subjective wellness scores for individual athletes. Individual and combined effects of these variables on injury risk were evaluated with generalized linear mixed models. Results: High cumulative loads and acute-to-chronic workload ratios were associated with increased risk of injuries. The effects for measures derived using exponentially weighted moving averages were greater than those for rolling averages. History of a recent injury, long-term experience at professional level, and substantial reductions in a selection of musculoskeletal screening and subjective wellness scores were associated with increased risk. The effects of high cumulative loads were underestimated by ~20% before adjusting for previous injuries, whereas the effects of high acute-to-chronic workload ratios were overestimated by 10-15%. Injury-prone players, identified via player identity in the mixed model, were at > 5 times higher risk of injuries compared to robust players (hazard ratio 5.4, 90% confidence limits 3.6–12) despite adjusting for training load and previous injuries. Combinations of multiple risk factors were associated with extremely large increases in risk; for example, a hazard ratio of 22 (9.7–52) was observed for the combination of high acute load, recent history of a leg injury, and a substantial reduction in the adductor squeeze test score. Conclusion: On the basis of our findings with an elite team of Australian footballers, the information from athlete monitoring practices in team sports should be interpreted collectively and used as a part of the injury prevention decision-making process along with consideration of individual differences in risk.
Keywords: injury prevention, athlete monitoring, training load, injury history, Musculoskeletal screening, Subjective wellness, Professional experience
Received: 30 Nov 2017;
Accepted: 24 Aug 2018.
Edited by:Hassane ZOUHAL, University of Rennes 2 – Upper Brittany, France
Reviewed by:Pascal EDOUARD, Centre Hospitalier Universitaire (CHU) de Saint-Étienne, France
Daniel Boullosa, Universidade Católica de Brasília, Brazil
Copyright: © 2018 Esmaeili, Hopkins, Stewart, Elias, Lazarus and Aughey. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Robert J. Aughey, Victoria University, Australia, Institute of Sport, Exercise and Active Living (ISEAL), Melbourne, Australia, firstname.lastname@example.org