Static body mass and parameters of aerobic capacities were investigated in 200 high performance athletes and 80 untrained persons. The results were subjected to a variant analysis. A subdivision of the athletes into strength and endurance sports has been shown to be of value. The mean range in untrained persons, strength athletes, endurance sports athletes and other athletes is presented. Significant variations were observed. Body mass, height and surface area was measured and the findings in athletes and untrained persons were compared. From the variant analysis of absolute and relative heart volume, the statement can be made, that athletes have larger hearts and that differences between sports exist. On the average the maximal O2-Puls and maximal Wattpuls as a measure of the aerobic capacity are greater in trained than in untrained persons. A close correlation between maximal O2-Puls and Wattpuls was demonstrated. Between strength and endurance athletes significant differences in both parameters are observed. A comparison of several statistics from the West German sport medicine literature of recent decades has shown, that in spite of changes in training quality and quantity in high performances athletes no evidence could be found for an increase in the performance parameters of the aerobic capacity.

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Excitability changes and glucose metabolism in experimentally induced focal cortical dysplasias.

Malformations of cortical development are increasingly recognized in association with severe epileptic syndromes, neuropsychological disorders and mental retardation. Several clinical and experimental studies suggest that functional consequences of cortical dysplasias are not restricted to the area of the dysplastic lesion but also involve remote brain regions. In the present study cortical malformations were induced in newborn rats at day of birth by intracerebral injection of the glutamatergic agonist ibotenate. The resulting cytoarchitectonic lesion associates neuronal depopulation of deep cortical layers, ectopic neurons in superficial layers and sulcus formation, mimicking human polymicrogyria and migration disorders. Electrophysiological recordings of evoked field potentials in slice preparations of adult animals reveal hyperexcitability in widespread cortical regions surrounding the dysplasia. Low-intensity stimulation induced epileptiform activity consisting of long-lasting, multiphasic and N-methyl-D-aspartate-dependent field responses. They appeared with high variability as all-or-none events. These widespread changes in excitability were not observed in sham-operated animals with small superficial ectopias but intact deep cortical layers, indicating that focal loss of these layers induces extended alterations in cortical connectivity and imbalance of excitation and inhibition. Restricted zones of increased excitability were also found in the forelimb and hindlimb representation cortex in sham-operated and control animals, demonstrating that this activity has to be considered as an intrinsic property of specific cortical areas. Deoxyglucose autoradiography showed that the widespread hyperexcitability in ibotenate-injected animals was not accompanied by alterations in glucose metabolism, although in the area of structural abnormality a typical metabolic pattern was found, revealing an increased glucose uptake in layer I. Hypometabolism as described for many types of human dysplastic lesions was not observed. This difference between the experimental and clinical data may be due to the absence of behavioral seizures in this model. However, it can be hypothesized that in patients with developmental malformations, additional pathogenic factors contribute to the manifestation of seizure disorders.

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