ABSTRACT
Skeletal muscle produces reactive oxygen species (ROS) and nitrogen species (RNS) continuously at rest. This production is substantially increased transiently by physical exercise and it is found chronically elevated in some diseases. During many years, ROS have been considered deleterious for cell function and strongly associated to aging process. At present, there is evidence that ROS, when found in low/moderate concentrations, play an important role in regulation of many cellular functions. ROS can cause both an improvement and impairment of cell functions depending on the intracellular concentrations and cellular antioxidant capacity. The purpose of the present chapter is to discuss the involvement of ROS in skeletal muscle function and dysfunction.
