a system for assessing a user &# 39 ; s movement capabilities creates an accurate simulation of sport to quantify and train several novel performance constructs by employing : proprietary optical sensing electronics for determining , in essentially real time , the player &# 39 ; s positional changes in three or more degrees of freedom ; and computer controlled sport specific cuing that evokes or prompts sport specific responses from the player . in certain protocols of the present invention , the sport specific cuing may be characterized as a &# 34 ; virtual opponent &# 34 ;, that may be kinematically and anthropomorphically correct in form and action . though the virtual opponent could assume many forms , the virtual opponent is responsive to , and interactive with , the player in real time without any perceived visual lag . the virtual opponent continually delivers and / or responds to stimuli to create realistic movement challenges for the player . the movement challenges are typically comprised of relatively short , discrete movement legs , sometimes amounting to only a few inches of displacement of the player &# 39 ; s center of mass . such movement legs are without fixed start and end positions , necessitating continual tracking of the player &# 39 ; s position for meaningful assessment . the virtual opponent can assume the role of either an offensive or defensive player .