Department of Sports Medicine and Nutrition, University of Pittsburgh, 3860 South Water Street, Pittsburgh, PA 15203, USA; Department of Psychiatry, University of Pittsburgh School of Medicine, 3501 Forbes Avenue, Suite 456, Pittsburgh, PA 15213, USA. Department of Psychiatry, University of Pittsburgh School of Medicine, 3501 Forbes Avenue, Suite 456, Pittsburgh, PA 15213, USA. Department of Sports Medicine and Nutrition, University of Pittsburgh, 3860 South Water Street, Pittsburgh, PA 15203, USA. Rooney Sports Medicine Concussion Program, Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, 3850 South Water Street, Pittsburgh, PA 15203, USA. Department of Physical Medicine and Rehabilitation, Harvard Medical School, 1575 Cambridge Street, Cambridge, MA 02138, USA. Department of Sports Medicine and Nutrition, University of Pittsburgh, 3860 South Water Street, Pittsburgh, PA 15203, USA. Electronic address: connaboy@pitt.edu.