1. Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill and North Carolina State University, 10304 Mary Ellen Jones Building, Chapel Hill, NC 27599, USA
2. School of Kinesiology, University of Michigan, CCRB 4745G, 401 Washtenaw Ave., Ann Arbor, MI, 48109-2214, USA
3. Orthopaedic and Rehabilitation Biomechanics Laboratory, University of Michigan, CCRB 4745G, 401 Washtenaw Ave., Ann Arbor, MI, 48109-2214, USA
4. Department of Physical Therapy – Program in Exercise & Rehabilitation Science, Marquette University, 604 N. 16th St. 215D, Milwaukee, WI, 53233, USA