Zinc, oxidative stress and physical activity

Abstract

During intense physical activity there is an increased production of reactive oxygen species that can cause muscle injury and damage to erythrocyte cell membranes, thus impairing athletic performance. In order to prevent the effects caused by oxidative stress, the organism has several antioxidant mechanisms, some of which depending on zinc. The antioxidant properties of this mineral are explained by its role in the regulation of metallothionein synthesis, in the structure of superoxide dismutase, and in the protection of sulfhydryl groups of cell membrane proteins through antagonism with pro-oxidant metals such as iron and copper. Recent studies have shown that the osmotic fragility of erythrocytes is related to the zinc function in cell membranes. Athletes generally have dietary zinc intakes inadequate to compensate for the increased sweat and urine losses to meet and the high biochemical demand. This paper reviews the biological and nutritional significance of zinc in the antioxidant protection during intense physical activity.