1. Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.
2. Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
3. Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.
4. Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
5. Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.