Pedaling for Parkinson’s -- Full Length Doctor's Interview
Jay Alberts, Ph.D., explains a new therapy for Parkinson's patients.
Reported August 13, 2007


How can exercise be beneficial for Parkinson's patients?

Dr. Alberts: Previous studies in the animal literature have shown great benefits for exercise in terms of improving Parkinson’s function and also help potentially be neuroprotective. These studies have been in the animal studies -- unfortunately there hasn’t been a lot of translation from the animal studies to the human studies. A lot of human studies haven’t shown significant improvements in motor function using the various human interventions, such as weight training or other types of exercise training.

How does the tandem intervention relate to the animal studies?

Dr. Alberts: There’s somewhat of a disconnect between these the animal studies and these somewhat inconclusive human studies. One of the things that we are looking at here is using a paradigm more closely resembling those used in the animal studies. The animal studies use a paradigm called forced exercise. Forced exercise requires the animal to exercise at a rate that’s faster than their voluntary rate. One of the notions behind the tandem intervention is that we are forcing the Parkinson’s patient to pedal at a rate that’s greater than their voluntary rate. One of the ideas, or hypotheses that we’re looking at, is maybe we’re driving their central nervous system beyond their normal capacity. And what we’re thinking is that this might change or lead to biochemical changes that underlie these improvements in motor function, or possibly lead to some neuroprotective element.

Does exercise change the biochemistry of the brain?

Dr. Alberts: The exciting thing for us is that we’re using a lower extremity exercise and we’re showing significant improvements in upper extremity function. So for us, that suggests that we’re changing the way the brain is actually functioning, because we’re not just improving the strength of the legs and measuring walking or postural stability -- we measure fine motor function of the hands, and it improves. We’re not quite sure what the mechanism is underlying that improvement, so right now my colleagues and I are engaged in studies to look at changes in the biochemical changes, and also to look at changes in brain activity with fMRI.

Is this a breakthrough for Parkinson's treatment?

Dr. Alberts: Absolutely. In many respects, we may be actually treating the disease rather than just treating the symptoms.

How did the tandem cycling study come about?

Dr. Alberts: I think there is an element of, “Why do we have these promising exercise studies in animals and they’re not being replicated in the human population?” One of the things that really led to this exercise study are some observations that we made on the road while we did a bike ride across Iowa in 2003, and then also last year, last summer in 2006. What we found, when a Parkinson’s patient rode a tandem with me, was their motor symptoms improved dramatically. So we starting asking ourselves, "What are the differences between a Parkinson’s patient riding their own bike and riding a tandem with an able-bodied cyclist?" And the main difference is the speed at which they pedal. A Parkinson’s patient typically pedals around 55-60 RPMs, whereas when they ride the tandem, or rode tandem with me, they’re pedaling between 80 and 90 RPMs. So in many ways, this tandem was like a forced exercise paradigm that was being used in the tandem studies. And the results we found on that trip really led to the development of this study.

What is forced exercise?

Dr. Alberts: We’re forcing the patient to exercise or pedal at a rate that’s faster than they can normally achieve on their own.

Are you changing how the central nervous system functions that way?

Dr. Alberts: Potentially. We don’t know the exact mechanism, but what we’re thinking is that because Parkinson’s patients have, for lack of a better term, decreased neural drive, so they may not be able to drive their system sufficiently. We are really augmenting their central nervous system or their ability to move their legs.

How much is this helping patients?

Dr. Alberts: So far, in terms of clinical results with the unified Parkinson’s disease rating scale, after 8 weeks of exercise, these measures have improved 30 percent to 35 percent for patients. That is pretty dramatic improvement, and it’s on the same magnitude as studies that look at the effects of deep brain stimulation. I’m not saying that this should take the place of deep brain stimulation -- there’s just a comparison for what type of improvement someone gets.

Do the preliminary results differ much from the effects of medication?

Dr. Alberts: The preliminary results are similar to the effects that we receive with medication -- that’s one of the things that we’re looking at with the fMRI study -- to see if exercise is producing a medication effect in terms of the network within the brain, how it’s functioning.

What kind of feedback are you getting from patients in the study?

Dr. Alberts: In general, it’s been pretty positive in terms of the patients' improved motor function and certainly increased level of energy. Certainly, the feedback has been very positive from the patients. A number of patients comment on how this intervention seems to improve their tremors.

Which symptoms are improving from this therapy?

Dr. Alberts: Tremor scores certainly are responding well to this intervention, as are other symptoms such as bradykinesia -- the slowness of movement and fine motor function. We’re also doing biomechanical testing and we’re showing improvements in hand function as well.

Why are you studying treatments like this when there are medications and treatments already out there, like deep brain stimulation?

Dr. Alberts: One of the reasons is this was an observation that we found on the road, and it was quite dramatic. So as a scientist, it intrigued me -- “What’s going on here? How can we replicate this in a laboratory setting?” The other reason is it’s a very simple intervention that doesn’t require a lot of fancy equipment or medications. There are side effects to medication and as one takes medications, their effectiveness tends to decrease over time. This may also be an adjunctive method to improve the effect of the medication. In terms of deep brain stimulation, I certainly do a lot of work in that area, but there are risks associated with the surgical implantation of the electrodes and there are some potential side effects with DBS as well. We don’t see any side effects here. We all know that exercise is good for you -- if we can improve brain function too, that’s pretty exciting.

Does medication change the brain's activity as well?

Dr. Alberts: The medication changes brain function as well, and so we’re using changes -- we have baseline data from patients when they’re on and off medication, and so now we’re looking at patients who exercise and then don’t exercise and try to compare the changes in brain activity between the two different states -- the medication state and an exercise state -- to see how they might be similar or different.

What is the ultimate goal?

Dr. Alberts: I guess the ultimate goal would be to develop an intervention -- most likely it would have to be a motorized bike or something because it’s probably not practical to use a tandem bicycle in the real world. We’re working with various companies to potentially develop a motorized bike that could be used in the patient’s home. My real goal is, and it goes back to this trip that we took in Iowa, is to help patients improve their quality of life. And if we can deliver a device or a system to them in their home, then I will feel relieved and extremely successful.

Are all Parkinson's patients affected by the disease in the same ways?

Dr. Alberts: Parkinson’s is an individual disease -- the progression is different for each patient and the motor symptoms are different for each patient. Hopefully, what we can find here is an intervention that is effective, or that effectively improves motor function for patients across the board. That’s one of the things that we’ll be looking at in future studies. The other thing is, we’re certainly looking at the amount, the dose necessary, how long and how effective these treatments are. So today, what we have found is that if the patients exercise for eight weeks, we’ve shown about a 30% to 35% improvement in clinical scores. After that 8-week period they stop exercising, and we follow them at a 2 week and a 4 week follow-up point. We’re seeing long term effects at both the 2 and the 4-week point, so that’s encouraging. There are these semi-permanent changes, whereas with medication -- if you stop taking medication -- the disease symptoms come back within a few hours. With deep brain stimulation, you turn the stimulator off and the symptoms almost come back immediately. We’re encouraged by these results and the fact that there are some semi-permanent changes potentially in the central nervous system. We’re following these up with fMRI studies and other biochemical measures.

This article was reported by Ivanhoe.com, which offers Medical Alerts by e-mail every day of the week. To subscribe, click on: http://www.ivanhoe.com/newsalert/.


This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc., or any medical professional interviewed. Ivanhoe Broadcast News, Inc., assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors in different ways; always consult your physician on medical matters.

Hi Carolyn,
I have just bought a motorised bike. It was fairly cheap, about $120. However, it has speeds of 30, 40 50 and 60 RPM, and Dr Alberts says you need 80 to 90 RPM. He says results show in 8 weeks, but he does not give any idea of how long each day you need the exercise. I only have time to do 10 minutes each day,
I think Gregg raised this one also.
Ron

i am having trouble understanding "forced exercise". how can you pedal faster than the fastest you can pedal?
are the feet strapped in?? if i was on a motorized thing it seems like my legs and knees would go all wonky(i love that term -all wonky) wouldnt the effect be the same if i just made myself pedal 80 rpm?

thanks