An exercise system/device for exercising a user's upper limb is described. The exercise system/device is intended for use in rehabilitating patients suffering hemiparesis that causes one upper limb to be at least partially paralyzed. For example, the exercise system/device can be used for neuroplastic retraining rehabilitation techniques for enabling patients to regain control of their paralyzed upper extremities, including shoulders, elbows, wrists and fingers, but primarily their shoulders and elbows via larger arm movements. This is achieved through the use of an elongate handle and a motion sensing device associated with the handle for communicating the user's movements of the handle to a gaming system. Although the exercise system/device is primarily for rehabilitation of patients suffering hemiparesis, it may also be used by any person for bilateral training and exercising upper limbs.