ABSTRACT
It is very likely that both during exercise and in the postexercise period, generation of reactive oxygen species (ROS) is markedly increased. There are several potential sources of ROS that can be activated by exercise. One of the most important sources is the mitochondrial electron transfer chain. It has been calculated that 2 to 4% of the total oxygen utilized in mitochondria may undergo only one electron reduction and escape the ubiquinone step.
