As per the experiments conducted by research teams in Colorado University (CU) subjects who were fitted with robotic arms, could achieve performance with lesser efforts with continued practice. For the purpose of the experiment, 15 subjects who were right handed were fitted with a robotic arm along with a handle similar to a joystick, which could control a cursor on the computer screen.
The subjects were made to perform various tasks such as inward and outward movements and reaching out to a particular target on the computer screen.
It was established that though the subjects learnt a reaching task and the stability in muscle activity was achieved, the amount of energy lost during the performance of the task kept reducing gradually as they kept practicing the movements. The amount of energy in terms of carbon dioxide exhaled and oxygen consumed reduced by 20% when the subject mastered the movements through practice. The subjects of the test were required to exert more energy when the robotic arm created a force field. Initially they were made to perform a series of 200 trials where there was no force field. Then the subjects were made to perform two sets of 250 trials each with the force field. It was found out that the subjects reduced the amount of energy spent by reducing errors. Other data that was collected included electromyographic data by studying the six upper limb muscles when the tasks were performed.
The results of this study could be applied for the rehabilitation of stroke patients who have to relearn how to walk.