1. R Humphrey, PT, PhD, FAACVPR, FACSM, is Assistant Professor, Department of Physical Therapy and Department of Physical Medicine and Rehabilitation, and Collateral Assistant Professor of Education, Virginia Commonwealth University, Medical College of Virginia Health Sciences Campus, 1200 E Broad St, PO Box 980224, Richmond, VA 23298 (USA).
2. R Arena, PT, is a doctoral student in the combined physical therapy/physiology program, Virginia Commonwealth University