“Research has shown that exercise can improve gait, balance, tremor, flexibility, grip strength and motor coordination.
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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.
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Beyond this, we know that people who exercise vigorously, for example by doing things like running or riding a bicycle, have fewer changes in their brains caused by aging.
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However, when it comes to exercise and PD, greater intensity equals greater benefits. Experts recommend that people with Parkinson’s, particularly young onset or those in the early stages, exercise with intensity for as long as possible as often as possible. Your doctor might recommend an hour a day three or four times a week, but most researchers think that the more you do, the more you benefit.
Scientists at University of Pittsburgh 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.
At the molecular level, at least two things are happening to make dopamine use more efficient:
1. Dopamine travels across a space between two adjacent brain cells called a synapse. This process is called signaling and it is essential for normal 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.
2. Secondly, they found that the cells receiving the dopamine signal had more places for the dopamine to bind in animals that exercised, and so could receive a stronger signal. This binding site is called the D2 receptor.
They also studied the D2 receptor in a subset of the human subjects who were within one year of diagnosis and not on any medications, using the imaging technique known as positron emission tomography(PET). They found that in humans, too, exercise increased the number of D2 receptors.”