To determine the effect of a novel movement strategy incorporated within a soccer warm-up on biomechanical risk factors for anterior cruciate ligament injury during 3 sport-specific movement tasks.
Single-blind, randomized controlled clinical trial.
Twenty top-tier female teenage soccer players.
Subjects were randomized to the Core Position and Control movement strategy (Core-PAC) warm-up or standard warm-up, which took place before their regular soccer practice over a 6-week period. The Core-PAC focuses on getting the centre of mass closer to the plant foot or base of support.
Peak knee flexion angle and abduction moments during a side-hop (SH), side-cut, and unanticipated side-cut task after the 6 weeks with (intervention group only) and without a reminder to use the Core-PAC strategy.
The Core-PAC group increased peak flexion angles during the SH task [mean difference = 6.2 degrees; 95% confidence interval (CI), 1.9-10.5 degrees; effect size = 1.01; P = 0.034] after the 6-week warm-up program without a reminder. In addition, the Core-PAC group demonstrated increased knee flexion angles for the side-cut (mean difference = 8.5 degrees; 95% CI, 4.8-12.2 degrees; ES = 2.02; P = 0.001) and SH (mean difference = 10.0 degrees; 95% CI, 5.7-14.3 degrees; ES = 1.66; P = 0.001) task after a reminder. No changes in abduction moments were found.
The results of this study suggest that the Core-PAC may be one method of modifying high-risk soccer-specific movements and can be implemented within a practical, team-based soccer warm-up. The results should be interpreted with caution because of the small sample size.
*Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada;
Departments of †Physical Therapy; and
‡Occupational Science and Occupational Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada;
§Department of Epidemiology and Preventive Medicine, Monash University, Victoria, Australia;
¶Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Saskatoon, Canada; and
‖Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada.
Corresponding Author: Janice J. Eng, PT/OT, PhD, Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada (Janice.Eng@ubc.ca).
Supported by an operating grant from the British Columbia Medical Service Foundation (BCM06-0007). Further support for this study was provided to J.J.E. in career scientist awards (Canadian Institutes of Health Research MSH 63617; Michael Smith Foundation for Health Research) and to R.G.C. in a Canadian Institute of Health Research Strategic Training Fellow in Rehab Research award.
The authors report no conflicts of interest.
The University of British Columbia Clinical Research Ethics Board approved the protocol for this study. ClinicalTrials.gov registration identifier number: NCT01591941.
Received December 12, 2012
Accepted August 06, 2013