NOVELTY - The method involves determining virtual velocity of a physical activity being simulated, where an estimate of a velocity occurs when the simulated physical activity force is applied by a user (101) during an actual physical activity. An actual velocity is determined based on a measured velocity of a movable component of a stationary exercise apparatus (100A). The actual velocity is compared with virtual velocity, and movement or resistance to movement of a treadmill belt (110) is controlled to simulate effects of changes in momentum based on the comparison of the velocities.    USE - Method for controlling a stationary exercise apparatus i.e. treadmill exercise apparatus, for sport-specific training for an athlete and for rehabilitation of a patient with leg injuries and cardiovascular conditioning of the patient. Uses include but are not limited to track and field athlete, football player, soccer player, basketball player, rugby player, baseball player, field hockey player and runner.    ADVANTAGE - The method targets the muscle fiber types and/or operates at extrema of a force-velocity-duration space of the athlete using sport specific motions and/or accurately measuring intensity of exercise, and for training the athlete requiring leg strength utilizing bipedal locomotion. The method accurately monitors the capabilities of the athlete in different modes of the bipedal locomotion motion involved with the athlete's sport. The method allows for the analysis of exercise performance through analysis of force and velocity data associated with the exercise in an efficient manner. The method provides the ability to target specific force-velocity-duration regimes and utilizes the targeting of specific force-velocity- duration regimes to develop specific metabolic processes.    DESCRIPTION OF DRAWING(S) - The drawing shows a cut-away side view of a stationary exercise apparatus having an aft harness.    Stationary exercise apparatus (100A)    User (101)    Treadmill belt (110)    Fore frame strut (115)    Distance sensor (116)