Exercise is an important part of healthy living for everyone. However, for people with Parkinson's disease (PD), exercise is not only healthy, but a vital factor in maintaining balance, mobility and activities of daily living (ADLs). The National Parkinson Foundation (NPF) is studying exercise in the Quality Improvement Initiative and believes that exercise plays a role in positive outcomes in patients PD, and the data supports that. Exercising is associated with a better sense of well being throughout all stages of the disease.
Benefits of Exercise for Seniors with PD
1. Symptom management: Research has shown that exercise can improve gait, balance, tremor, flexibility, grip strength and motor coordination. Physical activities such as treadmill training and biking have all proven beneficial, as have tai chi and yoga (although further research on these is needed).
2. Slowed disease progression. There is a strong consensus among physicians and physical therapists that improved mobility decreases the risk of falls and some other complications of Parkinson's. They agree that practicing movement through physical therapy sessions, occupational therapy, and participating in an exercise program improves mobility. By avoiding complications, patients can also avoid some of the things that can make Parkinson worse.
Beyond the physicial benefits, researchers have also found that people who exercise intensely, such as runners and bicyclists, have fewer changes in their brains caused by aging. Studies in animals suggest that the cognitive effects of Parkinson's disease are also improved by exercise.
Many neurologists in the NPF Center of Excellence network recommend intense exercise to their patients and also to people who are worried about developing PD due to a family connection. One neurologist recommends that individuals who have a relative with Parkinson's exercise 300 minutes a week, with at least half of this time devoted to intense running or bike riding.
How Exercise Affects the Brain
In PD, a special kind of brain cell (neuron) that produces the chemical transmitter dopamine gets damaged and lost. However, there is a lag between the time when the loss of neurons begins and the time when Parkinson's motor symptoms start to show. In fact, by the time most people are diagnosed, as much as 40-60 percent of their dopamine neurons are already gone.
The reason that people with Parkinson's don't experience symptoms until they reach this point is that the brain can compensate for the loss of dopamine neurons by gradually changing to adapt to the situation. In fact, the brain reshapes itself throughout life in response to various experiences. Scientists call this ability to change and compensate experience-dependent neuroplasticity.
So, what happens in the brain during exercise to produce physical and mental health benefits in PD patients? Researchers at the University of Southern California (Fisher et al.) looked at the brains of the mice that had exercised under conditions parallel to a human treadmill study. They found that exercising changed neither the amount of dopamine nor the amount of neurons in the animals' brains. However, the brain cells of the physically active mice were using dopamine more efficiently. They also found that exercise improves that efficiency by modifying the areas of the brain where dopamine signals are received — the substantia nigra and basal ganglia.
Scientists at University of Pittsburgh have also found that in animal models, exercise induces and increases the beneficial neurotrophic factors, particularly GDNF (glial-derived neurotrophic factor), which reduces the vulnerability of dopamine neurons to damage.
Dopamine travels across a space between two adjacent brain cells called a synapse. This process is called signaling and it is essential for normal neurological functioning. To end the signal, a protein complex called the dopamine transporter normally retrieves dopamine from the synapse. The first thing Fisher et al. found is that animals that had exercised possessed less of the dopamine transporter, meaning that dopamine stayed in their synapses longer, and their dopamine signals lasted longer.
Secondly, researchers found that the cells receiving the dopamine signal had more places for the dopamine to bind to in animals that exercised, and so these animals could receive a stronger signal. This binding site is called the D2 receptor.
They also studied the D2 receptor in a subset of human subjects who were within one year of PD diagnosis and not yet taking any medications. Researchers used the imaging technique known as positron emission tomography (PET) and found that in humans, too, exercise increased the number of D2 receptors in the brain.
How to Develop a PD-Friendly Exercise Plan
The best way to achieve these benefits is to exercise on a consistent basis. People with Parkinson's who enroll in exercise programs with durations longer than six months, regardless of exercise intensity, have shown significant gains in functional balance and mobility compared to programs of only two-week or ten-week durations.
However, greater intensity does equal greater benefits. Experts encourage people with Parkinson's disease, particularly young onset and those in the early stages, engage in high intensity exercise for as long as possible as often as possible. Doctors typically recommend an hour a day three or four times per week, but most researchers believe that the more patients work out, the more they benefit.
Intense exercise is defined as physical activity that raises one's heart rate and causes heavy breathing. Studies have focused on running and bicycle riding, but experts feel that other intense exercise regimens should provide the same benefit.
Regardless of a person's condition, a warm up period and proper cool down are crucial. Always exercise in a way that is safe for you, and know your limits. There are many support groups, therapists, and fitness experts who can help with finding or creating an exercise program for Parkinson's disease. Be sure to consult a physician before beginning a new regimen.
Many programs target the rapid gains that can be achieved through a focus on improvements in functional capacity and mobility. These programs vary according component activities. Examples of exercise programs for people with Parkinson include:
- Intensive sports training
- Treadmill training with body weight support
- Resistance training
- Aerobic exercise
- Alternative forms of exercise (yoga)
- Home-based exercise (workout tapes)
- Practice of movement strategies
Try Working Out with a Partner
Many people find that they achieve the most success when they work out with a partner. Depending on the stage of the disease, it may be best for people with Parkinson's to train in an environment where there are others around to offer help if needed.
Beyond supervision and assistance, peers can also help to motivate and encourage each other in their exercises. People who are new to exercise programs are generally best off working with an individual or group training leader. For people whose mobility is already significantly affected by PD, a physical therapist may be the best choice for helping to start a program.
Medical content reviewed by: Nina Browner, MD—Medical Director of the NPF Center of Excellence at the University of North Carolina at Chapel Hill in North Carolina and by Fernando Pagan, MD—Medical Director of the NPF Center of Excellence at Georgetown University Hospital in Washington, D.C.