Exercise and the Aging Brain

Abstract
The clinical landmarks of an aging motor system closely resemble diseases of the extrapyramidal system, notably the basal ganglia. Similarly, mechanisms that appear to be related to one of these diseases, Parkinson's disease, also seem to be related to motor system aging. The nigrostriatal dopaminergic system, impaired in both Parkinson's disease and in aging, has been shown to be substantially involved in movement initiation. This involvement has been shown by analyzing nigrostriatal dopamine in fast vs slow responding animals, and by manipulating the dopaminergic system by pharmacological methods. Exercise may postpone the deterioration in response speed that is generally observed in the aged motor system, by maintaining the nigrostriatal dopamine system. This mechanism is suggested by differences in neurotransmitter function seen in exercise rats compared to sedentary rats, and in studies of dopamine metabolites obtained from exercised humans. These mechanisms suggest that an excellent physical condition may very well postpone the emergence of symptoms of an aging motor system. Exercise may also have ameliorative effects on the symptoms of Parkinson's disease.