Exercise as it relates to Disease/High intensity eccentric resistance training decreases bradykinesia in Parkinson's disease patients

This page investigates and critiques the research and findings of "High intensity eccentric resistance training decreases bradykinesia and improves quality of life in persons with Parkinson's disease: A preliminary study"1.

Background of Research
Parkinson’s disease is a medically diagnosed chronic disease where the central nervous system is affected. Known as a movement disorder, Parkinson’s is characterised by muscle rigidity and/or tremors, a lack of core stability and a reduction in reaction time5. Though there is no known reason for the onset of this disease, these symptoms are bought on when the brain reduces the production of Dopamine, particularly in the basal ganglia. Dopamine is the neurotransmitter that allows messaging interaction between cells in the brain. When this chemical is reduced, it becomes much harder to control movements making everyday life more difficult.

One of the major problems in everyday life for Parkinson’s patients is the slowness of movement, otherwise known as Bradykinesia. Usually, people are able to change the velocity of their movements in varying degrees from isometric to ballistic contractions. However, this level of 'control' is unable to be maintained by those with Bradykinesia and the abnormality in ballistic movement is one of the key determining features for those with Parkinson's2.

As there is no cure for this disease, just as important as finding the reason for onset, the most practical action that can be taken is to improve the quality of life for these individuals and minimise the impact it takes emotionally and psychologically3,4. Some level of reversibility in Bradykinesia would benefit everyday movement in sufferers with Parkinson's by reducing the difficulty of simple tasks1. This study looked at how high intensity eccentric resistance training can induce adaptations in muscle contraction force produced, improving functional movement and speed in the hope that Bradykinesia is at least partially reversed and perceived quality of life is increased for those with Parkinson's.

Where is the Research from?
Funding for this study was provided by the University of Utah and the Foundation of Physical Therapy. The paper was published by Elsevier and is available online to purchase.

Type of Research
The experiment used the method of a randomised control trial to distinguish a measurable difference between the two groups. This technique evaluated the effectiveness of high intensity eccentric resistance training on Bradykinesia in Parkinson’s persons.

To measure the severity of the participants motor deficiency, the Unified Parkinson’s Disease Rating Scale was used. With a maximum score of 108 in the test, higher scores indicate higher severity. This was used to evenly distribute individuals into the control or experiment group.

In the analysis of the data, analysis of variance (ANOVA) distinguished the correlation between the high intensity eccentric resistance training and improvements in the four tests. Level of significance was set at p<0.05.

What did the Research Involve?
This research involved a total of nineteen participants with varying degrees of Parkinson's disease to conduct a set of pre and post tests specific to difficulties caused by the disease. These included muscle force, gait speed, timed up and go and a questionnaire. Once they were assigned into each of the two groups, each individual participated in the initial tests.

Ten of the participants engaged in high intensity eccentric training for twelve weeks which involved conducting three sets of five second unilateral voluntary maximal isometric contractions on a dynamometer. Between each contraction there was a three minute rest period. The remaining nine were part of the active control group.

After the twelve week period, the nineteen participants conducted the same four tests, which were compared to the first set. Analysis of variance was used to determine significance in the results.

Conclusion from the Research
The hypothesis presented by the researchers of this paper “that PD-related bradykinesia was in part reversible, and that high intensity loading of the quadriceps associated with our experimental group would result in amplified benefit in terms of increased movement speed and QOL relative to the active control group” was shown to be correct. If a cheaper and more accessible alternative to an eccentric ergometer could be found, this method could be a safe and effective way to induce beneficial adaptations to a wider population of sufferers with Parkinson’s disease.

Though there was an increase in muscle force and gait speed, as well as a reduction in time taken for the Timed Up and Go Test and MQR-39 score (all beneficial to PD persons), there was no statistical significance between individuals with differing severities of the disease.

Practical Advice
Though the findings of this research show support for the intervention of eccentric resistance training to reduce Bradykinesia in Parkinson's patients, the improvement in quality of life showed no significance in severity of the UPDRS motor score. Therefore, is it beneficial for Parkinson's individuals to undertake this training if there is no improvement subjectively?4 Further research is needed to determine if a cheaper and more accessible alternative option provides the same improvements as the eccentric ergometer. This type of training could then become more available to the wider Parkinson's disease population and benefit a greater number of people.

Further Information/Resources
Featured Paper: Paper Parkinson's Disease: Parkinson's Australia. Exercise Tips: [http://www.parkinson.org/understanding-parkinsons/treatment/exercise/tips Exercise Tips from the NATIONAL PARKINSON FOUNDATION. ]

University of Utah Physical Therapy: UofU