Abstract des Autors

Endurance stress mainly needs aerobic energy supply and is dependent on increased supply of oxygen. Highly reactive products (hydroperoxides) caused by the reduction of molecular oxygen must be eliminated to minimize cellular membrane structures being attacked by radicals. Animal experiments have shown that the lack of vitamins and selenium can lead to enhanced damage of cellular membranes (nucleus, mitochondria, microsomes). The enzyme glutathione peroxidase having selenium as essential cofactor, together with superoxide dismutases and vitamin E as cell protection complex counteract this cell destruction process. We took blood samples of 13 test persons before, immediately after and 2 hours following a marathon course. Our experiments have shown that throughout all means, the selenium level of the plasma (41-153 micro-g/l) and the vitamin E concentration of the serum (12,5 +/- 3,2 mg/l) were within normal range. Although the muscle enzymes after the marathon course were enhanced they did not show any significant changes compared with similar marathon strains. Based on these results we conclude that the probands had sufficient blood concentrations in terms of the antioxidants selenium, vitamin A, E and beta-carotine. We could not observe an increased release of muscle enzymes due to enhanced cell permeability or cell damage. Verf.-Referat