Aerobic Exercise for Parkinson’s Disease: Benefits and Prescription Based on Research
Aerobic exercise is defined as prolonged, rhythmic activities that utilize large muscle groups. We’ve discussed some of the general guidelines for aerobic exercise in our previous blog post. In this post, we will discuss the research on aerobic exercise and Parkinson’s Disease and then give a summary of the recommendations for aerobic exercise to learn a bit more about what aerobic exercise does and why it is so helpful for people with Parkinson’s Disease. Spoiler alert: Aerobic exercise helps create brain change!
So why is aerobic exercise so helpful? There are so many reasons to participate in some form of aerobic exercise such as:
to maintain a healthy weight
reduce general health risks such as heart disease, high blood pressure, type two diabetes, and stroke
improve aerobic capacity
improve immune health.
If that’s not enough to convince you, aerobic exercise has also been shown to improve physical functioning, quality of life, and functional capacity in individuals with Parkinson’s Disease (Duchesne et al, 2015). But wait, that’s not all! Aerobic exercise has been show to create brain change through a process call neuroplasticity. Neuroplasticity is the process of brain change and includes neurons creating new connections, or synapses, as well as strengthening connections, changing them, and rewiring areas of the brain.
Evidence of Brain Change
One marker for Parkinson’s Disease severity is low corticomotor excitability meaning a lower response from the nerve cells in the brain to a given stimulation. But the good news is, research has shown that aerobic exercise (specifically treadmill training) can increase corticomotor excitability and improve walking speed in individuals with Parkinson’s Disease. (Fisher et al, 2008).
Another study used PET imaging to look at dopamine receptors in individuals with Parkinson’s following a treadmill walking protocol. They found that treadmill walking increased the dopamine D2 receptor density. This means that aerobic exercise can help increase the number of dopamine receptors therefore allowing dopamine to bind easier, and medications to work better! (Fisher et al, 2013).
Brain Derived Neurotrophic Factor (BDNF) is a neurotransmitter or chemical messenger that is released in response to exercise. More and more research is coming out showing the positive impact of aerobic exercise in individuals with Parkinson’s Disease due to the release of BDNF which is a major driver for brain change! Research on animal models of exercise and PD have shown that continuous treadmill exercise increases levels of BDNF in areas of the basal ganglia (substantial nigra pars compacta - the specific area that releases dopamine!). In human studies, they have found that stationary cycling caused an exercise induced increase in BDNF levels as well as a significant improvement on the UPDRS (the exam your neurologist uses to measure how you are doing!). (Zoladz et al, 2014 & Marusiak et al, 2019).
Aerobic Exercise to Slow Disease Progression
While there are many medications to help manage the symptoms related to Parkinson’s Disease, there is not a medication that is proven to slow the progression of Parkinson’s Disease. Recent research has been focused on whether or not aerobic exercise can help to slow Parkinson’s progression and the results are very exciting!
In 2018, a literature review was published by the Mayo Clinic that looked at whether or not aerobic exercise can help slow Parkinson’s Disease. Based on the studies they reviewed, here are some key take away points:
Exercise facilitates neuroplasticity - this means that exercise helped the brain to form and modify connections between nerve cells. This helps to counter neurodegenerative disease and brain aging.
Regular exercise is associated with less cognitive decline in individuals with Parkinson’s Disease
Regular exercise reduces the risk of lateral developing dementia and cognitive decline. In people that had already developed a cognitive impairment, regular exercise reduced the severity of the impairment.
Fitness level was associated with larger hippocampal volume. The hippocampus is an area of the brain that plays a large role in memory.
Intensity Matters!
Now that we have discussed all of the amazing benefits of aerobic exercise, let’s talk a little bit more about how to actually implement it! It’s important to remember that the intensity of exercise matters (this is one of the 10 principles of neuroplasticity). You can’t just get on a stationary bicycle and cycle at an easy speed and expect to slow disease progression.
We measure the intensity of exercise a few different ways. One way is by calculating a target heart rate and monitoring your heart rate throughout exercise. For moderate to high intensity exercise, your target heart rate is at about 50-85% of your maximum heart rate. To calculate your maximum heart rate, a simple way is to subtract your age from 220. Below is a table with some guidelines for target heart rate.
Another way to monitor the intensity of exercise is by using a rate of perceived exertion scale. On a scale from 0-10, you should be exercising around a 4-6/10 for moderate intensity exercise.
There is a lot of research on forced exercise for individuals with Parkinson’s Disease. What this means, is exercising at a higher intensity than what is comfortable. One randomized controlled trial looked at forced exericse through tandem cycling. They had trainers on a stationary tandem bike with an individual with Parkinson’s. The trainer forced the individuals with Parkinson’s to pedal at least 80-90 revolutions per minute and keep their heart rate between 65-80% of their maximum heart rate. They compared functional MRI and UPDRS scores for individuals that were off medications, on medications, and individuals that were off medications but had completed forced exercise. They found that there were similar patterns of brain activation in those that had taken medications and in those that were off medication but had completed forced exercise. Additionally, there was a 37% improvement in the UPDRS motor exam for the group that was on medications, while there was a 48% improvement for the group that was off medications but had completed forced exercise. The take away message here, is that when you are doing aerobic exercise, be sure to monitor your intensity and find a safe way to complete moderate to vigorous exercise rather than doing was feels comfortable. (Albers, 2016).
This table shows the improvements in UPDRS motor scores for the individuals that were on medications, as well as the individuals that were off medications but completed forced exercise. Exercise is medicine!!! (Albers, 2016).
Below is a table summary of the recommendations for aerobic exercise. If you aren’t sure where to start, get in touch with your doctor or physical therapist, or try joining one of our exercise classes so we can help!
Sources:
Ahlskog, 2018. Aerobic exercise: Evidence for a direct brain effect to slow Parkinson’s Disease progression. Mayo Clin Proc 93(3): 360-372.
Albers et al, 2016. Cortical and motor responses to acute forced exercise in Parkinson’s disease. Parkinsonism Relat Disord 24: 56-62.
Duchesne et al, 2015. Enhancing both motor and cognitive functioning in Parkinson’s disease: Aerobic exercise as a rehabilitative intervention. Brain Cogn 99: 68-77.
Zoladz et al, 2014. Moderate intensity interval training increases serum brain-derived neurotrophic factor level and decreases inflammation in Parkinson’s disease patients. J Physiol Pharmacol 65(3): 441-8.
Marusiak et al, 2019. Eight weeks of aerobic interval training improves psychomotor function in patients with Parkinson’s disease - Randomized controlled trial. Int J Environ Res Public Health 16(5): 880.