Abstract: An actively controlled exercise device provides a dynamic force responsive workout. The device includes: a user output arm movably attached to a base frame; an actuator attached between the user output arm and the base frame, the actuator including a motor and an output shaft connected to the user output arm; at least one position sensor attached to the actively controlled exercise device adjacent to the user output arm for detecting a position and velocity of the output arm; a load cell attached to the actively controlled exercise device adjacent to the actuator for detecting a force exerted on the user output arm; and a force controller in communication with the position sensor, the load cell, and the actuator for activating the actuator to impart a force on the user output arm during an exercise repetition.