1. a Center for Human Movement Science, Division of Physical Therapy , University of North Carolina , Chapel Hill , North Carolina , USA
2. b Department of Physical Medicine & Rehabilitation, School of Medicine , University of Virginia , Charlottesville , Virginia , USA
3. c Sports Biomechanics Laboratory, School of Human Movement Science , Beijing Sports University , Beijing , China
4. d Sports Medicine Center , Duke University Medical Center , Durham , North Carolina , USA