Return to search

The influence of movement speed on the ability to learn reaching movements in health and after stroke

Fast movements have traditionally been avoided during rehabilitation after stroke for fear that they might increase spasticity. However movements in daily life require alterations in speed. In healthy individuals (n=14), 1 week of intensive reaching training in a robotic manipulandum biased participants movement speed during other tasks performed in the manipulandum: people who trained to move slowly tended to move more slowly whereas the opposite was true for the fast training group. Yet the improvement in movement accuracy was the same in both groups. In chronic stroke survivors (n=37) functional ability before training was determined by muscle stiffness and weakness. Endpoint accuracy improved after training at both movement speeds in all participants apart from those with the greatest sensory impairment. However, training at the different speeds modified different kinematic parameters of the task (e.g. movement trajectory versus velocity profile) so that training at one speed did not generalise well to movements performed at non-trained speed. Most interestingly muscle stiffness was not increased by training at high velocity. Unexpectedly, it was reduced and functional ability as well as the ability to reach outside of the robotic manipulandum improved. Transcranial magnetic stimulation on a sample of these stroke participants (n=19) was used to test the hypothesis that ipsilateral drive to proximal muscles from the non-stroke hemisphere is important in determining recovery of arm and shoulder movement. MEPs could be elicited in at least 25% of muscles from both hemispheres but contrary to expectation, arm function was only correlated to the drive from the affected hemisphere, even in patients with the greatest impairment. Muscle activation patterns were not significantly different between the affected and unaffected limb and training did not alter these. Training at a fast speed is not detrimental in patients after stroke and should be encouraged to increase the variety of movements patients can perform.

Identiferoai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:639699
Date January 2015
CreatorsHammerbeck, U.
PublisherUniversity College London (University of London)
Source SetsEthos UK
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Sourcehttp://discovery.ucl.ac.uk/1461801/

Page generated in 0.002 seconds