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- To Mark Hirsch Here are a few thoughts re a subject you raised - Excercise and PD - I believe there is a definite relationship between certain effects of exercise and PD. The primary benefits are not in the area of retraining or mental well being but are direct therapeutic consequences of adrenaline mediated activity. Thus, I would speculate that the most impacting activity would be sustained vigorous (aerobic) excercise or situations which result in sustained anxiety. These effects are mediated by the autonomic nervous system which is commonly divided into two modes; 1. the lie down and be loved mode and 2. the fight or flight mode. The benefits of the aforementioned activities seem to be a consequence of exhausting the latter mode, (depletion of norepinephrine? transient unresponsiveness of norepi receptors? , effects of endorphins? or direct influence on the dopamine system). In the presence of dopamine the exagerated response to the ANS fight or flight mode results in increased tone in the muscles and clinicaly as dyskinesia, in the absence of dopamine it increases the severety of akinesia. Here's an analogy; imagine a motorized articulated machine, in the presence of dopamine the articulations are rusty so the movement is non fluid, herky jerky - oiling thse joints (blue filter or visual cues) results in more normal function. in the absence of dopamine, the gas pedal is depressed but the brakes are also engaged, dopamine or visual cues releases the brakes. I have observed that frequently as long as 24hours after vigorous excercise or a prolonged period of anxiety rich activity I will get an increase in the duration and degree of dyskinesia. This is a positive sign indicating that what is ordinarily the appropriate dose of L-Dopa is now excessive. If one is conscious of this response and reduces the dose there is a qualitative and quantitative response - sometimes dyskinesia can be completely suppressed for 6 to 8 hours. In fact I sometimes think of dyskinesia as a body that is fighting but without cognitive control - instead of a coordinated controlled explosion of muscle activity e.g. a punch, one gets uncontrolled flailing of muscle activity i.e. dyskinetic motion. An interesting study would be to test my belief that it is possible to temporarily but immediately rationalize this irrational muscle activity by consciously applying cognitive control - choreographed aerobic exercise, shadow boxing, running. The blue filter phenomenon is useful because it tends to facilitate the suppression of the fight or flight mode and augment the lie down and be loved mode. I don't see how wearing them while excercising could augment the therapeutic benefits of excercise, however, it is possible that their anti dyskinetic effect could be augmented if they were used after excercise. An important study would be to test whether sustained suppression of dyskinesia (via visual cues) extends the duration of action of a dose of l-dopa Finally, you made a comment about how voice training can affect gait. In my experience it is just the opposite, gait enablement can imnpact on voice. best wishes, tom riess