Exercise Is Not Optional, It Is Mandatory.

Exercise is Not Optional, it is Compulsory

Copied from SPRING Times No 40. Page 14-16.

 

The World Parkinson Congress, the first of its kind, took place from February 22nd to 26th, 2006 at Washington Convention Centre, USA, attracting some 3,200 participants, 1,100 of whom were patients or caregivers.

The Congress supported by the Movement Disorder Society, the National Institute of Health, U.S. Army Medical Research Acquisition and over 100 professional and patient organizations from all over the world, was unique not only in size and scope but also in that it brought together patients, caregivers and many of the world’s leading Parkinson’s experts, doctors and scientists.

Michael Kelly, a SPRING member, who attended the Congress, has written this article for SPRING Times.

With almost 200 papers to choose from, it was not an easy task for me to select those that might be of special interest to patients. In taking the subject of exercise as being worthy of special attention, I have singled out three papers for comment based on the following criteria:

 

·           Scientific importance of medical information

·           Originality of content

·           Immediate relevance for patients

 

The three papers are supplemented by an addendum, based on work currently in progress at the University of Frankfurt. Taken together, the material presented provides good grounds for a major re-evaluation of the role of exercise in patient therapy.

In the first talk entitled how exercise affects the brain: Towards a rationale for exercise-induced protection, Dr Michael Zigmond from the University of Pennsylvania spoke about the benefits of exercise, pointing out that it has been accepted for a long time that exercise is recommended for people suffering from numerous conditions, including cardiovascular problems and diabetes. He referred to the fact that studies carried out showed that the incidence of Alzheimer’s disease, stroke and PD was lower for those who exercised regularly compared to control groups.

The question is: What is it about exercise that confers a benefit? The work of Dr Greeno at the University of Illinois was referred to. He has been testing, a) animals walking fast or running, b) animals having to balance on a tightrope to obtain food, and c) couch potato animals relaxing all day. It has been found that running very significantly increases blood vessel density in the brain, with enhanced flows of blood improving the supply of nutrients and facilitating removal of waste. Furthermore, the tightrope group showed an increase in the number of synapses and overall, exercise increased the supply of survival or trophic factors. Running or fast walking had no effect on synapses and tightrope walking had no effect on blood supply. So, the type of exercise taken; needs to be considered, when designing a program. Reference was made to the work of Dr Carl Cotman at the University of California, showing that there is an increase in survival factors in the brain with exercise.

The question then becomes: what kind of exercise is needed and how much? The answer is: “lots of different types of exercise”.

Dr Zigmond then went on to talk about an animal model using the 60HDA neurotoxin (6 hydroxy dopamine). In a series of elegantly designed experiments using rats (referred to by Dr Zigmond as animals with front-wheel-drive) with individual forelimbs immobilized in casts and thus with the rat being forced to use a particular limb, it could be shown that forced exercise prior to or immediately after lesioning, with 6OHDA and continued for 7 days, could completely counteract the toxic effects of 6OHDA. Video clips of this phenomenon were shown for various configurations and provided an impressive demonstration of the benefits of exercise. If exercise was initiated seven days after lesioning, no beneficial effects occurred. Dr Zigmond could give no precise data on how long the effects lasted and how intensive the exercise had to be. This aspect will be referred to later.

 

The second talk with the somewhat unwieldy title: The effect of high-intensity exercise using body-weight supported treadmill training on neuroplasticity and functional recovery in individuals with Pd was given by Dr Beth Fisher from the University of Southern California. Dr Fisher has been involved for some years in translating over animal movement research for use in human applications. She spoke about the re-modeling that the brain is capable of, pointing out that, in recent years, a much greater degree of plasticity has been found to exist than was formerly thought to be the case. This applies not only to animal models but also to stroke and spinal injury models.

Dr Fisher reported on studies of mice using MPTP (a neurotoxin, causing immediate damage to dopaminergic neurons) in which one group receiving MPTP was exercised intensively for 30 days, a second group receiving MPTP did no exercise and a third group exercised without receiving MPTP. It was found that the MPTP group, which was forced to exercise, caught up with the non-MPTP exercise group and, in terms of speed and endurance, could match them after 30 days. This provides powerful evidence of the benefits of exercise in an animal model.

 

For exercise-testing of patients, use was made of a treadmill with an overhead bodyweight-support suspension harness to allow high-intensity exercise without any danger of falling or injury. Patients were divided into three groups: a high-intensity exercise group with MET 3.5 and above, a low-intensity group with MET below 3.0 and a no-exercise control group (1 MET=1kcal/kg, h). Testing was carried out in 24 sessions, each of 60 minutes duration, over a period of 8 weeks.

The outcomes of the exercise were measured in terms of changes in disease severity, functional performance (stair climbing, stand/sit movements) and brain function testing. This latter test, carried out using Trans-cranial Magnetic Stimulation (TMS) techniques, provided the most significant indications of the benefits of exercise. At various levels of stimulation, TMS was used to provide a Motor Evoked Potential (MEP) response, with peak-to-peak maximum amplitude and cortical-spinal rest time (Silent Period Duration, SPD) being measured independently in both brain hemispheres. This enabled a comparison to be made between the more the less affected sides in Pd patients and between Pd patients and healthy controls. SPD tends to be shortened and MEP shows higher peak-to-peak rest values (hyper excitability) in Pd.

 

Comparison between pre- and post-exercise readings showed that exercise led to a convergence to normal values in Pd patients, with the higher intensity exercises having the greatest effect.

 

A third very engaging talk entitled, 'People with Pd should have weekly Parkinson exercise classes for the rest of their lives', was given by John Argue from San Francisco. John is a former actor and, for the past 23 years, a physical therapist, working with People with Pd.

His approach to exercise and movement is a very practical one, using the activities of everyday life to counteract the restrictions imposed by Parkinson’s. A book he published in 2000 has sold over 20 000 copies and he now has a DVD out containing details of this program.

As an actor, John is able to slip into the role of a Person with Pd (PwP) and gave a completely convincing performance in terms of posture and movement. His somewhat unconventional approach to physical therapy involves three main headings: Stretching – as a preventive measure, countering foreshortening and restrictions of movement, Strength – to prevent muscle atrophication and to maintain ability to perform movement, along the lines of ‘use it or lose it’, Movement strategy – managing movement such that one is mindful of the sequence of actions required to complete the execution of a task. Examples shown included motion sequences associated with sitting down on a chair, rising from a supine position etc. Such sequences are executed automatically, when a person is healthy, but can pose severe problems for a PwP.

 

 John’s program involves 10 lessons, the first 5 of which are performed lying or sitting. Video clips with examples of straight stretch, rotational stretch, tilt side stretch etc. were shown.

Very early on in therapy, PwPs are given fall training, long before falls become a factor in disease progression. Patients are shown how to protect their face and head and how to mitigate the effects of falling.

John emphasized the importance of group therapy, not only in terms of the fellowship created among patients and benefits accruing from getting a sense of control over the disease, but also in as far as it gives caregivers time to rest and recuperate.

 

Addendum: As a spin-off from programs developed for performance improvement of top-class athletes, the University of Frankfurt has been carrying out extensive testing on the effects of various types of motion stimuli. One such program has been aimed at off-season training supplementation for downhill alpine skiers. This has led to development of the so-called Zeptor, a treadmill-like device with two oscillating footplates. This has been in use for past 2-3 years in specialized Parkinson clinics in Germany. Extensive tests in Germany and in Spain have shown it to have positive effects due to interactions between variable-intensity semi-stochastic (random) oscillations and neuro-muscle systems.

Dr Haas, a researcher in the Institute of Sport Medicine in Frankfurt University, has reported on tests showing that exercise/movement of a particular type can lead to nerve growth factors (NGF) being released by nerve cells (through activation of muscle sensors referred to as spindles). NGF initiates a cycle leading to enhanced formation of proteins, thereby assisting in neuron survival and growth. Increased physical activity is thus found to protect nerves but NGF release is dependent on the type and range of movement. Exercise carried out while standing have little or no effect on NGF, swimming has a small effect and treadmill exercises give good results. To achieve the best results, exercises should meet the following criteria:

 

·      Be quasi-rhythmic but with a stochastic element (a degree of randomness)

·      have a frequency of 1-10 Hz, about 5 Hz is optimal

·      involve a learning situation (complexity) and, if possible,

·      have an element of spatial variability.

 

Swimming is apparently too slow to be of major benefit but jogging/walking fast* (over uneven ground) would seem to come close to the ideal. Completely rhythmic or repetitive movements (such as might arise for example when holding a pneumatic tool) lead only to fatigue, with no beneficial effects on the nervous system. To get maximum physiological and neurological benefit, it would appear to be important to exercise on a regular basis because muscular degeneration begins within some days of stopping exercise.

The exercise sessions should involve a challenging degree of intensity, duration and complexity, factors that will vary widely depending on the abilities and impairment status of the individual.

 

Summary: While the benefit of exercise has been appreciated for many years, only in recent times has research begun to unravel the mechanisms underlying this phenomenon and to provide a differential evaluation of what different kinds of exercise can do. Findings that exercise can counteract the effects of neurotoxins and can lead to increases in nerve growth factors are especially encouraging. By establishing a solid basis for the benefits of exercise, it is hoped that patients on a wider front will be encouraged to include it as an integral part of their daily routine.